Breakfast Casserole

This make ahead breakfast casserole combines crusty bread, browned sausage, eggs, cheddar, spinach, peppers, mushrooms, and onions in one generous pan. You can turn it into an egg bacon breakfast bake with cooked bacon or assemble it as an overnight breakfast casserole for Christmas morning. The result gives you a reliable breakfast casserole for a crowd without early-morning stove duty. Prepare this easy make ahead breakfast casserole with eggs and bacon for brunch, holidays, or any morning that deserves more sleep.

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Prep Time 20

Cook Time 45

Total Time 1 30

Servings: 12 servings

Course: Breakfast

Cuisine: American

Calories: 212

Ingredients Equipment Method Notes

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 g arlic 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

Equipment

9x13 baking dish
Large skillet
Whisk
Rubber spatula

Method

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.

Recipe Notes

Make Ahead:
Assemble the casserole up to 24 hours ahead and refrigerate before baking. The cooked sausage and vegetable mixture can also be prepared up to 24 hours ahead and refrigerated.

Freezing & Reheating:
Freeze the assembled, unbaked casserole for up to 3 months. Thaw overnight in the refrigerator, bring to room temperature, and bake as directed. You can also freeze the baked casserole for up to 3 months. Thaw covered for about 24 hours, remove the plastic wrap, and bake at 350°F (177°C) for 25–30 minutes.

Bread:
Use crusty sourdough or another hearty bread. If using fresh bread, cube it and bake at 300°F (149°C) for 10 minutes to dry it slightly.

Potato Option:
Replace the bread with about 3 cups (380g) frozen diced hash browns. No thawing is needed. Fresh diced potatoes should be cooked in 1 tablespoon olive oil for about 10 minutes before using.

Meat:
Use sausage, ham, ground turkey, beef, or chicken. Pre-cooked meats only need to be chopped and added to the vegetables. For bacon, use 1/2 pound, cook separately, drain, and combine with the vegetables.

Vegetables:
Replace the peppers, mushrooms, or spinach with broccoli, zucchini, squash, or kale. Cook the vegetables before layering.

Vegetarian Option:
Omit the meat and add 1 extra cup of vegetables.

Milk & Cheese:
Half-and-half or whole milk gives the richest texture, but lower-fat or dairy-free milk works. Use your favorite cheese or a blend, such as cheddar, pepper jack, feta, Swiss, or smoked gouda.

Half Recipe:
Halve all ingredients and bake in a 9×9-inch pan for about 32–36 minutes.