A delicious overnight sausage and egg breakfast casserole that's prepared the night before, and ready to bake in the morning!
Looking for more breakfast recipes? Consider trying my French Toast Roll-Ups or Strawberry Crepes!

What I love about this breakfast:
- No mess or work in the morning! Just wake up and pop it in the oven, making it the perfect breakfast for Christmas morning, baby showers, brunch, or even just a regular busy weekday!
- Leftovers reheat great to enjoy for several days.
- Easy to adapt based on your own preferences.
How to make Overnight Breakfast Casserole:
Prepare pan by lining the bottom of a 9×13” pan with slices of white bread. (I've found that plain old white sandwich bread works best).

Sprinkle cheese on top of bread. (I use medium cheddar or Colby jack, but feel free to experiment with your favorite kind of cheese!)

Add browned sausage, onions, bell peppers and green chiles on top. (The green chiles add great flavor, and a little bit of spice. Feel free to substitute a mild salsa).

Whisk eggs in a mixing bowl. Add milk, salt, paprika, oregano, black pepper, garlic powder, and dry mustard and whisk well to combine.

Stir the egg mixture as you pour it evenly all over the top of the assembled casserole. Cover baking dish and place in the refrigerator overnight (or refrigerate for at least 6 hours).
Bake (uncovered) for 50-60 minutes or until center is set and outside edges are golden brown. Cool for 15 minutes before serving. I like to serve it with fresh avocado slices, to balance out the flavors.

Freezing Instructions:
To Freeze: Prepare the full recipe, but don't bake it. Cover pan with plastic wrap and then aluminum foil and freeze for 2-3 months. Allow to thaw overnight in the refrigerator, then let it come to room temperature before baking according to recipe instructions.
Recipe Variations:
- Veggies: Add more veggies or different veggies, like mushrooms or spinach. Use your favorite kind of cheese, if you'd like!
- Salsa: Substitute salsa for the green chilies.
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Recipe

Overnight Egg and Sausage Breakfast Casserole
Ingredients
- 6-8 slices white bread , crust removed
- 4 cups freshly shredded colby jack cheese , or cheddar cheese
- 12 ounces pork sausage
- 1/4 medium onion , chopped
- 1/2 red bell pepper , chopped
- 4 ounce can diced green chiles
- 6 large eggs
- 2 cups milk
- 1 teaspoon Kosher salt
- 1/2 teaspoon paprika
- 1/2 teaspoon Dried oregano
- 1/2 teaspoon freshly ground black pepper
- 1/4 teaspoon garlic powder
- 1/4 teaspoon dry mustard
Instructions
- Remove the crust from the bread slices. Lightly butter or grease a 9×13” baking pan.
- Arrange the bread slices in the baking dish to cover the bottom of the pan, with no spaces.
- Brown sausage in a skillet over medium heat, breaking it up into small pieces. Drain Grease and remove to plate.
- Add onions and bell peppers to skillet and saute until slightly tender, 3-5 minutes. Add green chiles.
- Sprinkle freshly grated cheese evenly over the the bread in the 9×13” pan. Add the cooked sausage evenly on top, followed by the onions, bell pepper, and green chiles.
- Whisk the eggs in a medium sized mixing bowl. Add milk, salt, paprika, oregano, black pepper, garlic powder, and dry mustard and whisk well to combine.
- Slowly stir the egg mixture as you pour it evenly all over the top of the assembled casserole. Cover baking dish and place in the refrigerator overnight (or refrigerate for at least 6 hours)
In the morning:
- Preheat oven to 350 degrees F. Bake (uncovered) for 50-60 minutes or until center is set and outside edges are golden brown.
- Allow to cool for 15 minutes before cutting into it and serving.
Notes
- Veggies: Add more veggies or different veggies, like mushrooms or spinach. Use your favorite kind of cheese!
- Salsa: Substitute salsa for the green chilies.
Nutrition
Adapted from Our Best Bites
HAVE YOU TRIED THIS RECIPE?!
RATE and COMMENT below! I would love to hear your experience.
I originally shared this recipe November 2017. Updated August 2021.
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We love this breakfast casserole. I added bacon as well and did 2 cups of Colby Jack and 2 cups of sharp cheddar. My go to from now on for Christmas morning too.
I made this today for brunch and it was fabulous. I played with it a bit and added more eggs and spinach. I upped the spices a bit also. Everyone raved about it. It was so easy and fast also. Thank you. It will be our Christmas morning breakfast this year!
Amazing recipe. So, I hate it when people say they changed it up & then rate it, but I think my changes aren’t truly changes (except for 1). I used sourdough wheat bread slices; I used chili & smoked paprika Hill’s pork sausage; I used 2 leeks instead of onion; I used pepper jack cheese instead of cheddar to make up for no green chilies; I didn’t use paprika b/c it was in the sausage I used; I didn’t use mustard b/c my hubby hates it (only true change). IT WAS AMAZING. will try with other sausage flavor & different cheese; Red bell pepper a must. served to guests – 4 of us ate the entire thing.
Can I cut the recipe in half to make for 6 people?
Your recipies look and sound yummy! Love it, as I didn’t have to sign on, follow, or give my e-mail before I could look,thank you!!!
I love your recipes. Very easy thanks for sharing
Very yummy! I add 9-10 eggs to make it fluffier. So good and I love to have leftovers to freeze.
Same! Up the amount of eggs
Can you freeze the leftovers?
Yes you can. Make sure they are cool and place them in a freezer safe bag. Reheat in mircowave.
Can i use ham to replace sausage?.
Yes that’s fine.
Made this last Christmas. Made again yesterday for this mornings breakfast. This time I added two extra eggs and only used 2 cups of cheese. Much lighter, didn’t miss the cheese one bit. Yum!
I tripled the recipe, can I still use one 13×9 pan.
No, you’ll need 3 pans.
I want to make this for dinner tonight. Would 5 hours in the fridge be long enough?
I think should be fine.