Each slice of this easy egg breakfast casserole is thick, flavorful, and satisfying; plus, the recipe is an incredibly convenient breakfast choice since it’s make-ahead and infinitely adaptable. Like quiche and breakfast egg muffins, you can use your favorite seasonings and cheeses, vegetables like peppers and mushrooms, meats like sausage or bacon, or you can make it vegetarian. The best part is that you can assemble this dish ahead of time so breakfast is a breeze in the morning!
Breakfast casserole is an all-in-one hearty meal that can be made ahead of time, feeds a crowd, reheats well, and makes great leftovers. My family devours it. For all these reasons and more, I’ve made it nearly 100x (no exaggeration there) for breakfast, brunch, and, yes, dinner. It’s one of my favorite Easter brunch recipes to serve each year, too.
I originally published this recipe in 2015 and have simplified it over the years. Let me show you how it comes together so you too can experience this crowd-pleasing superhero meal.
This Easy Breakfast Casserole Is:
- Adaptable to whatever vegetables, meats, cheeses, and herbs you have on hand.
- Easy to make ahead of time.
- Quick to throw together.
- Great as a quick weekday meal or a lavish weekend or holiday brunch.
- Excellent for entertaining a crowd.
- Made with some bread to soak up moisture, but potatoes work too!
- Ready for your favorite egg toppings like salsa, pico de gallo, green onion, cilantro, parsley, avocado, everything bagel seasoning, hot sauce, etc.
4 Main Components
When gathering ingredients for this recipe, I like to think of it as having 4 separate components. From there, you can have fun with variations.
- Vegetables
- Meat (or extra vegetables)
- Starch for soaking up moisture
- Egg, cheese, & milk mixture
Here Are the Endless Add-ins & Flavor Options
- Vegetables: Select which vegetables you’d like in the dish. Generally, the most popular with guests is bell peppers, spinach, and mushrooms. But I’ve also made this with broccoli/peppers, kale/mushrooms, and spinach/zucchini. Try to stick to 3–4 cups of vegetables total. Cook the vegetables down with some flavor-enhancing onion and garlic.
- Meat: Guests usually prefer meat in the casserole, so I add sausage. Or try using ground turkey, chopped bacon, ground beef, or ground chicken. I usually purchase uncooked sausage for this and brown it with some dried rosemary or Italian seasoning to give it a little extra flavor, but that is optional. If the meat you’re using is pre-cooked, such as chopped ham or shredded chicken, you can mix it with the cooked vegetable mixture before layering it into the dish.
- Starch: Like when making sausage & herb stuffing, breakfast strata, and French toast casserole, the bread should be slightly stale so it can soak up moisture. Crusty sourdough is FANTASTIC here. You can also use homemade artisan bread, seeded oat bread, whole wheat bread, a loaf of French bread, crusty baguette, biscuits, bagels or homemade bagels, or even day-old croissants (have you tried homemade croissants?!). To make it gluten free, use gluten-free bread or potatoes.
- Eggs, milk, & cheese: Whisk a dozen eggs with a little half-and-half or milk and stir in some shredded cheese. Like the vegetables and meat, use whatever cheeses you like best, such as sharp cheddar, pepper jack, feta, and/or smoked gouda.
Variations: One of my favorite variations of this recipe is everything bagel breakfast casserole. It’s a BIG HIT and consistently gets rave reviews. Or try my different method/recipe for biscuit breakfast casserole with homemade biscuits baked right on top.
Can I Use Potatoes?
Yes, you can replace the bread with diced hash brown potatoes—the kind you find in the freezer section of the grocery store. Guests have *loved* this version. Use about 3 cups (around 380g) of hash browns in place of the bread. You could also peel and dice fresh potatoes, but you’ll need to quickly cook them on the skillet for 10 minutes before using in this dish.
Another wonderful make ahead option with fresh potatoes is this ham and potato casserole that is egg free, but just as delicious.
Do I Have to Use Bread?
Bread or potatoes, yes. Besides eggs, bread is the main ingredient. To avoid a spongey, wet dish, this breakfast casserole needs structure at the bottom. You see, when eggs bake, they release a lot of liquid. Chunks of crusty bread (or hash brown potatoes) soak up some liquid so the casserole is chunky and textured, not flat and wet. It’s almost like the way we need an English muffin with our eggs benedict—to help soak up all that eggy goodness.
If you’re looking for something without this starchy addition, crustless vegetable quiche or an easy frittata are great options.
In Pictures: How to Make Breakfast Casserole
First, place the pieces of bread (or potatoes) in the bottom of a greased 9×13-inch or any 3–4-quart oven-safe dish. I usually use (affiliate links) this glass pan or the pictured red ruffled baking dish, which comes in a set with other sizes—definitely a splurge, but I’ve found the quality to be excellent. Showing you the bread scattered in the pan as well as the optional potato substitution:
Set that aside and pre-cook your vegetables and meat (if the meat is not cooked already). You can do this all in 1 big skillet on the stove, adding onion, garlic, and optional herbs like dried rosemary or your favorite seasoning blend. As that’s sizzling on the stove, whisk the eggs, milk, and cheese together:
Now it’s time to assemble, and I’ve made this process a lot easier over the years. Spoon all of the vegetables/meat mixture on top of the bread. Pour the egg mixture all over that:
Success Tip: Refrigerate Overnight
At this point, you can either bake it right away or refrigerate the casserole overnight and for up to 24 hours. During this time, the flavors mingle together and the bread has a chance to soak up some of the liquid and flavor. Wake up and all you have to do is slide it into the oven. If you’re in a rush, I do recommend at least 30 minutes in the refrigerator before baking, if you can spare it!
Bake until the edges are golden brown. Because it’s so egg heavy, the casserole puffs up in the oven like a cheesecake and then sinks back down as it cools. Cool for 5–10 minutes before slicing and serving.
What to Serve With Breakfast Casserole
For side dishes, fresh fruit and yogurt are light, simple, and quick. For healthy recipe ideas, see my complete list of 30+ healthy breakfast recipes. However, if you’re entertaining—or if you have several hungry teenagers in your house— you’ll love pairing this breakfast casserole with:
- Easy Cinnamon Rolls
- Slow Cooker Cinnamon Rolls
- Pumpkin Cinnamon Rolls or Pumpkin Crumb Cake
- Banana Muffins or Blueberry Muffins
- Baked Oatmeal
- Sour Cream Coffee Cake
- Banana Bread or Zucchini Bread
- Apple Cider French Toast
- Dark Chocolate Raspberry Coffee Cake, a Cinnamon Roll Wreath, or Cranberry Cake (great options around the holidays)
Your brunch guests will be beyond satisfied. Yes, even the teenagers!
Print
Easy Make-Ahead Breakfast Casserole
- Prep Time: 20 minutes
- Cook Time: 45 minutes
- Total Time: 1 hour, 30 minutes
- Yield: serves 12
- Category: Breakfast
- Method: Cooking
- Cuisine: American
Description
This easy breakfast casserole is infinitely adaptable and you can find variations and suggestions in the recipe Notes below. The version written below with sausage, mushrooms, bell peppers, spinach, and cheddar cheese is generally the most popular with guests. You can assemble the entire dish and refrigerate for up to 24 hours before baking.
Ingredients
- 4 cups (175g or 6 oz) cubes of crusty bread*
- 1 teaspoon olive oil
- 1 pound ground pork sausage, casings removed*
- 1 teaspoon dried rosemary or Italian seasoning, optional
- 3/4 cup (100g) chopped yellow onion (1/2 of a large onion)
- 2 garlic cloves, minced
- 2 cups (275g or 9–10 oz) chopped bell peppers
- 1 cup (100g or 3 oz) sliced mushrooms
- 1 cup roughly chopped fresh spinach
- 12 large eggs
- 1/4 teaspoon salt
- 1/8 teaspoon freshly ground black pepper
- 2/3 cup (160ml) milk or half-and-half*
- 1 cup (100g or 3.5 oz.) shredded cheddar cheese
- optional garnish: green onion and/or chopped parsley
Instructions
- Grease a 9×13-inch or any 3–4-quart oven-safe dish. Arrange bread cubes in an even layer in bottom of pan.
- Heat olive oil in a large skillet over medium heat. Add sausage and rosemary/Italian seasoning, if using, and break up the sausage into bite-size pieces with a wooden spoon or rubber spatula as it begins to cook. Add the onion, garlic, peppers, mushrooms, and spinach and cook until everything has slightly softened and sausage is mostly cooked through, about 5–6 minutes.
- Remove sausage and vegetable mixture from heat and spread in an even layer on top of bread.
- Whisk the eggs, salt, pepper, milk, and cheese together. Evenly pour over sausage/vegetable mixture. Add another sprinkle of salt and pepper on top.
- Cover casserole with plastic wrap or aluminum foil and refrigerate for at least 30 minutes and up to 24 hours. (When ready to bake, allow to sit at room temperature for 10–15 minutes as oven preheats.)
- Preheat the oven to 375°F (191°C). Bake the casserole, uncovered, until the top is golden, edges are crisp, and a toothpick inserted in the center comes out clean, about 40–45 minutes.
- Cool for 10 minutes, then slice and serve.
- Leftovers keep well in the refrigerator for up to 5 days. Reheat in the microwave to your liking.
Notes
- Make Ahead Instructions: This is an excellent make-ahead recipe because you can assemble it before baking up to 24 hours in advance. See step 5. You can also cook the sausage and vegetable mixture up to 24 hours in advance, cover and refrigerate until ready to use.
- Freezing & Reheating Instructions: To freeze, prepare and assemble through step 5, cover with plastic wrap, then a layer of aluminum foil, and freeze for up to 3 months. Thaw overnight in the refrigerator, and then bring to room temperature before baking as directed. You can also freeze the baked casserole for up to 3 months and when doing that, I suggest baking it in a disposable aluminum pan. Cool completely, cover with plastic wrap, then a layer of aluminum foil. When ready to eat, thaw it for about 24 hours (covered) in the refrigerator, remove the plastic wrap layer, then bake in a 350°F (177°C) oven for 25–30 minutes.
- Special Tools (affiliate links): 9×13-inch Baking Dish or any 3–4-quart Oven-Safe Dish | Glass Mixing Bowls | Whisk
- Bread: Crusty sourdough is fantastic in this recipe, or use any crusty, hearty bread. The crustier or more stale, the better. If your bread is fresh and/or flimsy, cut into cubes and bake on a baking sheet in a 300°F (149°C) oven for 10 minutes. It’ll be slightly crisp and ready to use in this recipe. No need to wait for the bread to cool before layering into the baking dish.
- Using Potatoes Instead of Bread: You can replace the bread with diced hash brown potatoes—the kind you find in the freezer section of the grocery store. Use about 3 cups (around 380g) of frozen hash brown potatoes, no need to thaw. You could also peel and dice fresh potatoes, but you’ll need to quickly cook/brown them on a skillet with 1 Tablespoon olive oil over medium heat for 10 minutes before using.
- Sausage or Other Meat: If using pre-cooked sausage links or ham, cut into slices/chunks, and there is no need to cook either. Simply stir into the pre-cooked vegetables before layering into the dish. You can replace the sausage with ground turkey, beef, or chicken—simply pre-cook with the vegetables according to the instructions. If using bacon, I recommend reducing to 1/2 pound and cutting into bite-size pieces. Cook separately from the vegetables until browned. Drain, then mix with the vegetables before layering into the dish.
- Other Vegetables: Feel free to replace all or some of the bell peppers, mushrooms, and spinach with other vegetables such as chopped broccoli, sliced zucchini or squash, or kale. Pre-cook as directed.
- Vegetarian Option: You can leave out the meat and replace with another 1 cup of vegetables.
- Milk: For the richest, heartiest texture, I recommend half-and-half or whole milk. You can use lower-fat milk or dairy-free milk if desired.
- Cheese: I usually use a blend of regular and sharp white cheddar cheeses. Use whatever cheeses you like best, such as pepper jack, feta cheese, Swiss, and/or smoked gouda.
- Half Recipe: You can halve this recipe by halving all of the ingredients and using a 9×9-inch square pan. Bake time is slightly shorter, about 32–36 minutes.
Nutrition
- Serving Size:
- Calories: 212
- Sugar: 3.1 g
- Sodium: 343 mg
- Fat: 12.8 g
- Carbohydrates: 11.2 g
- Protein: 12.5 g
- Cholesterol: 205.4 mg
This was very tasty. I made a large portion with potatoes. I made a small portion without the sausage for my daughter who enjoyed the meatless version.
My family members all have very different tastes when it comes to the add-ins. What would you suggest for baking time if I make half the recipe and divide it into four dishes so I can customize it to everyone’s liking?
Hi Laura! We’re really not sure, so keep an eye on them in the oven – Bake until the top is golden, edges are crisp, and a toothpick inserted in the center comes out clean.
I have a grandson who is dairy intolerant. Can you suggest a substitute for the cheese?
Hi DeLane, you can leave out the cheese if needed, but the casserole will lose some flavor. We haven’t tested it, but there are vegan cheese options available in many grocery stores. Let us know what you decide to try!
Could I bake this at 350 degrees instead of 375? I only have one oven, and need to bake 2 casseroles at once. The other casserole calls for a 350 degree oven. Thank you!!
Hi Kate, you can bake this at 350 degrees if needed. We’re unsure of the exact bake time, but it will take bit longer. Keep an eye on it and bake until the top is golden, edges are crisp, and a toothpick inserted in the center comes out clean.
I made half the recipe. I did exactly as the recipe suggested. It was very watery.
Could gluten free dried savory croutons be used instead of bread or potatoes in this recipe?
Hi Linda, we haven’t tested it, but if the croutons are on the larger side, that should work. Please do let us know if you try it!
Big hit at my family Thanksgiving Brunch. Love that it is make ahead.
If I want to make half of this recipe, or a third of this recipe, is it possible to use an 8 x 8 pan? I am making it for a small family and we don’t need the full recipe.
Hi Katie, you can halve this recipe for the 8-inch square pan. We’re unsure of the exact bake time, but guessing around 30 minutes, however that depends on all the add-ins. Keep a close eye on it. Hope your family enjoys it!
Thank you, I did exactly what you said and it turned out fantastic! Our family loved it. We will be making this again!
Can leftovers be frozen?
You bet! See recipe Notes: You can also freeze the baked casserole for up to 3 months and when doing that, I suggest baking it in a disposable aluminum pan. Cool completely, cover with plastic wrap, then a layer of aluminum foil. When ready to eat, thaw it for about 24 hours (covered) in the refrigerator, remove the plastic wrap layer, then bake in a 350°F (177°C) oven for 25–30 minutes.
I’ve made this recipe, in multiple variations, many times! It is always a hit – everybody loves it!
I made this for coffee hour after worship one Sunday and it was a big hit. Everyone loved it. I got so many”That was so delicious” comments. I made it ahead of when I needed it and refrigerated for about 12 hours and then baked it.
This was my first time making a breakfast casserole, I was really nervous about how it was going to come out. It was fantastic!!! I used a French baguette, sausage (1lb), bacon (5 strips), slice mushrooms (I cut the slices in half 2cups), a bag of frozen bell pepper and onion mix(I cut any long pieces), fresh onion(1/3 cup), sharp cheddar cheese( 1 heaping cup), Italian cheese blend(1/2 cup), and Italian seasoning. Oh and of course the dozen eggs…..lol. I served it with picante sauce and sour cream. Thank you so much for a great but simple recipe, I will be using it again and trying different variations. We’re over the same old stuff so I’ll probably check out some more of your recipes for some dinner ideas also.
I would live to try this receipe for a large group in a week (20+ppl). Isaw a similar one wehere a person used Pillsbury grands (biscuits) as the base. Would that work here? And would it work if they were uncooked when everything is put together?
Hi Bree, biscuits would work well here, or you can try our biscuit breakfast casserole instead. Hope it’s a hit!
This recipe is a new favorite! It was so flavorful and had gorgeous texture. We did use hashbrowns instead of bread because someone at the brunch we brought it to is gluten free — it turned out beautifully! We’re definitely saving this one!
I made this recipe as written with one exception. I didn’t have any crusty bread so I substituted mini tater tots. It is so delicious. Thank you!
I LOVE, LOVE, LOVE this! I made half a recipe with Beyond Mince (fake ground beef), bell peppers, brussel sprouts and red potatoes. I diced the potatoes, as recommended, and cooked them up with the “meat,” onions, garlic, peppers and brussels for about ten minutes. It was fabulous!! I added some green olives in there before baking. My husband went nuts over it. There are endless ways to vary the recipe too. As usual, your recipes are incredible, Sally!
Baked this morning for my daughter’s family after they did a run. They loved it. I will definitely make it again. I used half n half and added a dash of Tabasco. I also doubled the other seasonings.
I’ve made this recipe before and it’s fantastic! I’d love to bring it to our friends’ lake house this weekend – but I don’t want to have to prepare and bake it there! Would it work if I prepare and refrigerate Thursday night, bake it Friday morning, let it cool and cover it well… then bring it to the lake and serve it Saturday morning?
Hi Liz, that will work great!
I am going to make this recipe but I want to use has browns but shoukd they be thawed and drained? Out of the bag, I think they may have too much liquid.
Hi Linda, some readers have used shredded hash browns with success. We usually use the diced frozen hash brown potatoes mentioned in the Notes–no need to thaw those.
I made two batches of this–one with turkey sausage and one without meat. For the latter one, I added a cup of grated zucchini, which I squeezed the moisture out of before cooking. Both came out great, to rave reviews by my guests. Thanks for this excellent recipe for feeding a crowd!
what can i use instead of bell pepper mushrooms and spinach? can i use bacon with sausage? and make this a meat egg and hash brown casserole?
Absolutely! This breakfast casserole is very customizable. See the blog post above for more flavor inspiration.
Have this in the oven right now with the intent of freezing it for a friend who’s having a baby next month. My ADHD brain only now read that you had recommended freezing the entire thing in a disposable aluminum pan to oven heat all at once. Is there a viable way I can freeze this per serving (and what would the reheat plan be?) to save the situation?
Hi Brad, you can follow the same instructions with whatever dish you’re using – you just won’t have your dish around to use while it’s in the freezer!
Everything about this went well but the sour sour dough bread seemed a bit too much. Followed recipe per directions.
This was REALLY good!! Going to make again and again!
This was perfection! Perfectly seasoned, filling and delicious!! Enjoyed with a side salad of spring greens. We will be having leftovers tomorrow with fruit salad. My husband must have mentioned 10 times how much he enjoyed this dish!!!
I’m a novice and if I can make this anyone can. My family absolutely loved it! I had to leave out mushrooms because my family doesn’t like them. Still fantastic!
What is the oven temperature for this recipe? Approximately how long in the oven?
Hi Kim, You will bake this at 375°F (191°C) for about 40-45 minutes uncovered, until the top is golden, edges are crisp, and a toothpick inserted in the center comes out clean. Please see the recipe above for complete directions.
This recipe sounds great. I would like to take it to a potluck where it needs to be in the oven for approximately 1 1/2 hours either during its initial baking or to keep it warm after baking. Can this be done and still turn out well?
Hi Rita, the casserole only needs 40-45 minutes at 350 degrees. However, you could turn the temperature down quite a bit just to keep it warm, if needed. Be careful not to overbake. Hope it’s a hit!
Great recipe. Have been eating for days! I used a combination of roasted sweet potatoes and sprouted grain bread for the base. Delicious and super easy.
Adding sweet potatoes sounds delicious. Did you roast them until done then add to the mixture?
This was delicious! Thank you, Sally. I peeled , chopped up, and sauteed golden potatoes in garlic infused olive oil for 10 minutes, like you suggested. They worked out just fine. I added orange peppers, green onions, mushrooms, spinach and reconstituted sun dried tomatoes. I added dried basil, oregano, hot pepper flakes, salt and pepper to all the vegetables as they cooked in the garlic infused olive oil. I used cheddar cheese with the egg and whole milk. I was able to let it chill in the refrigerator for 4 hours. We ate it with a salad , sourdough toast, and fruit cup. Yum!