Description

This Easy Make-Ahead Breakfast Casserole is a savory and satisfying dish perfect for busy mornings or brunch gatherings. Packed with crusty bread, flavorful ground pork sausage, sautéed vegetables, and rich cheddar cheese, it can be prepared ahead of time and baked fresh when ready. The casserole is hearty yet versatile, with optional herbs and garnish to personalize your breakfast experience.

Ingredients

Scale

Base

4 cups (175g or 6 oz) cubes of crusty bread
1 teaspoon olive oil

Sausage and Vegetables

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

Egg Mixture

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

Prepare the baking dish: Grease a 9×13-inch or any 3–4-quart oven-safe dish thoroughly. Arrange the crusty bread cubes in an even layer covering the bottom of the dish.
Cook the sausage and vegetables: Heat the olive oil in a large skillet over medium heat. Add the ground pork sausage along with the dried rosemary or Italian seasoning if using. Break the sausage into bite-sized pieces with a wooden spoon or spatula. Once the sausage begins to brown, add the chopped yellow onion, minced garlic, chopped bell peppers, sliced mushrooms, and roughly chopped spinach. Cook while stirring occasionally until the vegetables soften slightly and the sausage is mostly cooked through, approximately 5 to 6 minutes.
Layer the cooked mixture: Remove the sausage and vegetable mixture from the heat and spread it evenly on top of the bread cubes in the baking dish.
Mix the egg custard: In a large bowl, whisk together the 12 eggs, salt, freshly ground black pepper, milk or half-and-half, and shredded cheddar cheese until fully combined. Pour this egg mixture evenly over the sausage and vegetable layer in the dish. For added seasoning, sprinkle a little more salt and pepper on top if desired.
Refrigerate: Cover the casserole tightly with plastic wrap or aluminum foil. Refrigerate for at least 30 minutes and up to 24 hours so the bread can absorb the egg mixture. Before baking, allow the casserole to sit at room temperature for 10 to 15 minutes as you preheat the oven.
Bake the casserole: Preheat the oven to 375°F (191°C). Bake the uncovered casserole for 40 to 45 minutes or until the top turns golden, the edges become crispy, and a toothpick inserted into the center comes out clean.
Cool and serve: Let the casserole cool for 10 minutes to set before slicing. Garnish with chopped green onion or parsley if preferred and serve warm.
Store leftovers: Refrigerate any leftovers for up to 5 days. When ready to eat, reheat individual portions in the microwave to your liking.

Notes

You can substitute the ground pork sausage with ground turkey or vegetarian sausage for a different flavor or dietary preference.
If you prefer a dairy-free option, use a plant-based milk and cheese alternative.
Adding more herbs such as thyme or sage can amplify the flavor profile.
For extra crispiness, broil the casserole for the last 2 minutes of baking, watching carefully to prevent burning.
Ensure the bread cubes are slightly stale or toasted to prevent the casserole from becoming soggy.
This casserole can be prepared entirely the day before to save time on a busy morning.

Prep Time: 20 minutes
Cook Time: 45 minutes
Category: Breakfast Casserole
Method: Baking
Cuisine: American

Keywords: breakfast casserole, make-ahead breakfast, sausage breakfast casserole, baked egg casserole, easy breakfast recipe