This overnight breakfast casserole with sausage, potatoes, eggs and cheese is easy to assemble the night before and bake in the morning. It’s perfect for a holiday breakfast or when you have overnight guests!
Need more ideas for easy breakfast recipes? Try my breakfast casserole in crockpot, crescent roll breakfast casserole or overnight French toast casserole.
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Best Breakfast Casserole Recipe
If you’re looking for an easy make ahead breakfast recipe that serves a crowd, this overnight breakfast casserole is perfect for you! It can be made the day before just like my favorite or breakfast strata or tater tot breakfast casserole.
Unlike other breakfast casserole recipes you may have tried, it’s so flavorful from the breakfast sausage and green chiles. Just like this egg and potato breakfast casserole you can prep it the day before, refrigerate it overnight and bake it in the next morning!
Why This Recipe Works
- Make ahead. The beauty of overnight breakfast casserole recipes like this or my eggs benedict bake is that all the hard work is done in advance!
- Feeds a crowd. Big enough for 8 generous servings, this overnight sausage breakfast casserole can feed a crowd. I love to serve it with berry fruit salad and silver dollar pancakes.
- A holiday favorite. This easy breakfast casserole recipe is perfect to serve for a Christmas morning breakfast or Easter brunch!
Ingredients for Breakfast Casserole
Find the full printable recipe with specific measurements below.
- Sausage: Breakfast sausage adds great flavor and protein.
- Veggies: Chopped onions, bell peppers, potatoes (diced or shredded) and green chiles are sauteed in butter, making them perfectly tender and flavorful. I also like to sneak in some chopped spinach before baking.
- Eggs: Make sure you’re using large, fresh eggs for the best flavor and texture. These get mixed with a little bit of milk to make them creamier, as well as a dash of salt and pepper.
- Cheese: A sprinkle of shredded cheddar cheese on top is the perfect finishing touch for this sausage breakfast casserole. It gets nice and melty as it bakes!
Substitutions and Variations
This overnight breakfast casserole with sausage is such a versatile dish that can be adapted to fit your needs.
- Protein: You can substitute baked ham or bacon for the sausage. Try chorizo for some Mexican flavor.
- Cheese: Substitute a different type of cheese like sharp cheddar cheese, Monterey jack, colby or mozzarella.
- Veggies: Swap in different veggies like mushrooms, broccoli or chopped asparagus depending on what you have on hand.
- Potatoes: Instead of diced potatoes, feel free to use hash browns like I did in this breakfast hashbrown casserole. So easy and customizable!
- Salsa: Use salsa instead of green chilis if you would like.
How to Make Overnight Breakfast Casserole
- Sauté. Brown sausage and add to a bowl once finished. Add butter to the same skillet and saute onions, bell peppers and potatoes until tender. Pour in green chiles, and cooked sausage. Transfer the mixture into a buttered 9×9″ baking dish and place in the fridge to chill slightly.
- Pour. In a medium bowl, whisk together the eggs, milk, salt and pepper. Then pour the eggs over the sausage mixture in the baking dish.
- Top. Next, sprinkle spinach over the top. Then add the shredded cheese. Cover with foil and store in the fridge overnight.
- Bake. When ready to bake, preheat the oven to 325°F and bake for 45 minutes. Remove foil and bake additional 10-15 minutes, or until toothpick comes out clean. Before serving, let stand for a few minutes to set completely.
5 star review
“Delicious & easy!! Skipped the green chilies (couldn’t find any) and left out the cheese (this way, family could add whatever cheese that they wanted after it was done baking in the oven), and it turned out great. Family loved this. Will make again.”
– Jane
Recipe FAQs
Once prepared, this overnight breakfast casserole can be stored in the fridge for about 24 hours before baking. I bring it slightly to room temperature before putting it in the oven by removing it from the fridge 30 minutes prior to baking.
It will be done when the outside edges are slightly golden and the egg mixture stays firm when you gently rock the pan from left to right.
You want to make sure the egg mixture has cooked all the way through and isn’t still liquefied in the center. To double check, stick a knife in the middle of the casserole. The knife should come out clean if cooked completely.
You can serve plain, or add toppings such as sliced avocado, salsa, cilantro or sour cream.
If you’re hosting a big brunch for a crowd and are looking for more dishes to serve alongside this breakfast casserole, a few ideas include rainbow fruit kabobs, homemade biscuits and breakfast potatoes.
Storing Leftovers
- Storing: Any leftovers will keep in the fridge for about 3-4 days. Make sure to cover your pan with a lid or wrap tightly in aluminum foil or plastic wrap.
- Reheating: You can either warm for a few minutes in the microwave or the oven. If using the oven, I would recommend covering with foil so the top doesn’t brown too much.
Looking for more easy breakfast ideas? Try my breakfast casserole with biscuits, cheesy ham and broccoli frittata or this delicious sausage breakfast pizza.
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Overnight Breakfast Casserole
Video
Ingredients
- ½ pound breakfast sausage
- 2 Tablespoons butter
- ½ cup chopped onion
- 1 cup chopped bell peppers
- 1 ½ cups frozen potatoes (cubed or shredded, thawed)
- 4.5 ounce can chopped green chiles
- 8 large eggs
- ⅓ cup milk
- 1 teaspoon Kosher salt
- ¼ teaspoon ground black pepper
- ½ cup chopped spinach (optional; add more if desired)
- ½ to 1 cup shredded cheddar cheese
Instructions
- Butter a 9×9" (or 8×10") baking dish and set aside. Cook the meat in fry pan over medium heat. Once cooked through, remove to a bowl.
- Add butter to the pan with the onions. Cook for 2 minutes. Then add the bell peppers and cook an additional 2 minutes.
- Next mix in the potatoes and cook until heated through, about 3 minutes. Stir in the sausage and green chiles and then pour into the baking dish. Place in the refrigerator to cool slightly, before adding the eggs.
- Whisk the eggs, milk, salt and pepper in bowl. Then pour over the sausage mixture in the baking dish.
- Sprinkle chopped spinach over the top. Next add the cheese. Cover with foil and then refrigerate until ready to bake.
- When ready to bake, preheat the oven to 325°F. Set the pan on the counter while the oven is preheating. Then bake for 45 minutes. Remove foil and cook an additional 10-15 minutes, or until a toothpick comes clean. Let stand a few minutes before serving and then slice.
Notes
- Meat: You could also substitute with ground turkey or Italian sausage. You could even substitute with diced ham or bacon too.
- Vegetables: Feel free to add in any vegetables you’d like. Some of my favorites to add are mushrooms, chopped asparagus or broccoli.
Nutrition
Nutrition provided is an estimate. It will vary based on specific ingredients used.
Did you make this recipe? Don’t forget to give it a star rating below!
Categorized as: American, Breakfast, Christmas, Easter, Eggs, Gluten-Free, Make Ahead, Nut-Free, Savory Breakfast
Jamielyn Nye is the founder and recipe creator at I Heart Naptime. She is the author of the I Heart Naptime Cookbook and shares easy family-friendly recipes and desserts for every occasion.
This is one of my favorite breakfasts to make for the holidays! It’s easy and SO delicious.
It’s so yummy! So glad you like it!
Such a perfect day starter!! Everyone at my house loved it!
I’ve made this so many times I can’t even count. It’s my go to to bring to brunch, for birthdays and holidays too!
Thanks for the review! It’s such a yummy dish to share with others :)
Love this recipe! So yummy and so nice that you can prep it ahead of time. I’m not usually a big breakfast person but I love when I have leftovers of this in the fridge!
you say this can be made ahead of time and served the next day…do we completely make it…like BAKE it and then REHEAT or just have all the ingredients raw/wet and poured into dish and then refrigerate and bake it the next day?
Hi Cindy! I prepare all of the ingredients raw/wet and then refrigerate and bake in the morning!
How do you make it ahead?
Hi Rose! You can prepare the breakfast casserole the day before, refrigerate it overnight and then pop it in the oven in the morning.
Do you know how many eggs if you made a 9×13? Thanks!
Hi Emily! I would double the recipe for a 9×13, so 16 eggs!
What’s the shelf-life of this? I travel a lot and make the coming weeks meals on the Sunday before, so 3-5 days is great. For this recipe, I will likely use bacon or ham.
Thanks!
This recipe freezes well! I would recommend cutting into squares and wrapping each one in foil or plastic wrap and then storing in an airtight container in the freezer. It will last a couple months. :)
Delicious & easy!! Skipped the green chilies (couldn’t find any) and left out the cheese (this way, family could add whatever cheese that they wanted after it was done baking in the oven), and it turned out great. Family loved this. Will make again.