Make-Ahead Breakfast Casserole with Sausage
Breakfast casserole with sausage, eggs, bread, and sharp cheddar that you assemble the night before and bake in the morning. Feeds a crowd of 12.
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Breakfast casserole is the recipe that saves Christmas morning, the first day of school, and honestly a lot of Tuesday nights at my house. Pork sausage, eggs, bread cubes, and sharp cheddar go into a 9×13 the night before, sit in the fridge overnight, and slide into the oven while everyone is still waking up. You get an hour back on a morning when you need it.
The overnight rest is doing real work here. Bread cubes need hours to drink up the egg custard all the way through, and a casserole assembled and baked in the same hour comes out with dry bread floating on top of a wet layer underneath. Day-old bread soaks it up even better, since it has already dried out and is thirsty for the custard.
We eat this for dinner about as often as we eat it for breakfast. Serve it with a green salad and some sliced fruit and nobody at my table complains that eggs turned up at six in the evening.
Why You’ll Love This Breakfast Casserole Recipe
- All the work happens the night before. Twenty minutes of prep after dinner, then all you do in the morning is turn on the oven.
- Cheesy and rich. Three cups of sharp cheddar melt through the whole pan, layered in instead of just sprinkled on top.
- It feeds twelve. One 9×13 covers a houseful of overnight guests or gives you leftovers all week.
- Breakfast for dinner, sorted. It’s hearty enough to be the whole meal with just a salad alongside.
Breakfast Casserole Ingredients
Sturdy day-old bread is the one ingredient worth planning for. French bread, sourdough, or a rustic white loaf hold their shape after soaking overnight, while soft fresh sandwich bread collapses into a paste under all that custard.
- 2 tbsp butter, softened, for the dish
- 1 lb ground pork breakfast sausage
- 1 yellow onion, diced
- 1 red bell pepper, diced
- 10 cups day-old French bread, cut into 1-inch cubes (about a 1 lb loaf)
- 3 cups shredded sharp cheddar, divided
- 10 large eggs
- 2 1/2 cups whole milk
- 1 tbsp Dijon mustard
- 1/2 tsp garlic powder
- 1 tsp salt
- 1/2 tsp black pepper
- 2 tbsp fresh chives, sliced, for garnish
Recipe Variations
- Swap the sausage for a pound of chopped bacon or diced ham; both cook down the same way.
- Use frozen shredded hash browns in place of the bread cubes, about 6 cups, thawed and squeezed dry.
- Stir in 2 cups of chopped baby spinach with the onion and pepper for a little green.
How to Make Breakfast Casserole
- Butter the dish: Rub the softened butter over the bottom and sides of a 9×13-inch baking dish.
- Brown the sausage and vegetables: Cook the sausage in a large skillet over medium-high heat for 7-8 minutes, breaking it apart, until no pink remains and it reaches 160°F. Add the onion and bell pepper and cook 4-5 minutes more, until softened. Drain off the excess fat.
- Layer the pan: Spread half the bread cubes in the buttered dish. Scatter half the sausage mixture over them and sprinkle with 1 1/2 cups of the cheddar. Repeat with the remaining bread, sausage, and cheddar.
- Whisk the custard: Whisk the eggs, milk, Dijon mustard, garlic powder, salt, and pepper together in a large bowl until completely smooth and no streaks of white remain.
- Soak overnight: Pour the custard evenly over the pan and press the bread down with a spatula so every cube is wet. Cover tightly and refrigerate at least 4 hours, or overnight.
- Bake: Pull the breakfast casserole out of the fridge 30 minutes before baking and heat the oven to 350°F. Cover with foil and bake 30 minutes, then uncover and bake 25-30 minutes more, until the top is golden, the center is puffed, and a thermometer in the middle reads 160°F.
- Rest and serve: Let it sit for 10 minutes so it sets up, then scatter the chives over the top and cut into squares.
Recipe FAQs
Can I Bake It Right Away Instead of Refrigerating Overnight?
You can, but give it at least 30 minutes on the counter first so the bread absorbs some custard. Baked immediately, the top layer stays dry and the bottom stays soggy.
How Do I Know When a Breakfast Casserole Is Done?
The center should be puffed and set with no jiggle, and a thermometer in the middle should read 160°F. If the top browns before the center sets, tent it with foil and keep going.
Can I Assemble and Freeze It Unbaked?
Yes. Wrap it tightly and freeze up to 2 months, then thaw overnight in the fridge before baking as written. Baking from frozen makes the edges overcook before the middle sets.
Can I Use Half-And-Half Instead of Whole Milk?
Absolutely, and it makes a richer custard. Anything lighter than whole milk gives you a thinner, more watery set.
Can I Cut the Recipe in Half?
Yes, halve everything and use an 8×8 dish. Start checking at 35 minutes total, since a smaller pan bakes faster.
Cooking Tips
- Press the bread down into the custard before it goes in the fridge, and again in the morning. Cubes that float stay dry and toast into croutons instead of soaking.
- Layer the cheese in the middle as well as on top. Cheese only on top browns into a lid and never makes it into the middle of the pan.
- Take it out of the fridge 30 minutes before it bakes. A cold glass dish going straight into a hot oven can crack, and the center takes forever to catch up.
Storage and Freezing
To store: Cover leftovers tightly and refrigerate for up to 4 days.
To freeze: Baked squares freeze well for up to 2 months. Wrap them individually and thaw overnight in the fridge for the best texture.
To reheat: Warm a whole pan, covered with foil, in a 325°F oven for 20 minutes. Single squares reheat in the microwave in about 90 seconds.
How to Serve Breakfast Casserole
Breakfast casserole is a full plate on its own, though sliced oranges, berries, or a simple green salad round it out depending on the time of day. A pitcher of orange juice for brunch or a bowl of salad for dinner covers both directions. This is one of the recipes in our August collection, and more make-ahead casseroles like it are on the way.
Loved This Recipe?
Breakfast casserole is the rare dish that turns a chaotic morning into a calm one, and it does most of its work while you sleep.
Leave a star rating in the comments below, it helps other people find this recipe. Made it? Tag @allwellfed on Instagram, I love seeing this one in other people’s kitchens.
Make-Ahead Breakfast Casserole with Sausage
Ingredients
- 2 tbsp butter softened, for the dish
- 1 lb ground pork breakfast sausage
- 1 yellow onion diced
- 1 red bell pepper diced
- 10 cups day-old French bread cut into 1-inch cubes, about a 1 lb loaf
- 3 cups shredded sharp cheddar divided
- 10 large eggs
- 2 1/2 cups whole milk
- 1 tbsp Dijon mustard
- 1/2 tsp garlic powder
- 1 tsp salt
- 1/2 tsp black pepper
- 2 tbsp fresh chives sliced, for garnish
Instructions
- Butter the dish: Rub the softened butter over the bottom and sides of a 9×13-inch baking dish.
- Brown the sausage and vegetables: Cook the sausage in a large skillet over medium-high heat for 7-8 minutes, breaking it apart, until no pink remains and it reaches 160°F. Add the onion and bell pepper and cook 4-5 minutes more, until softened. Drain off the excess fat.
- Layer the pan: Spread half the bread cubes in the buttered dish. Scatter half the sausage mixture over them and sprinkle with 1 1/2 cups of the cheddar. Repeat with the remaining bread, sausage, and cheddar.
- Whisk the custard: Whisk the eggs, milk, Dijon mustard, garlic powder, salt, and pepper together in a large bowl until completely smooth and no streaks of white remain.
- Soak overnight: Pour the custard evenly over the pan and press the bread down with a spatula so every cube is wet. Cover tightly and refrigerate at least 4 hours, or overnight.
- Bake: Pull the breakfast casserole out of the fridge 30 minutes before baking and heat the oven to 350°F. Cover with foil and bake 30 minutes, then uncover and bake 25-30 minutes more, until the top is golden, the center is puffed, and a thermometer in the middle reads 160°F.
- Rest and serve: Let it sit for 10 minutes so it sets up, then scatter the chives over the top and cut into squares.
