Easy Make-Ahead Breakfast Casserole Recipe
This easy make-ahead breakfast casserole combines crusty bread, savory sausage, vegetables, eggs, and cheese to create a hearty and delicious morning meal. Perfect for brunches or busy mornings, it can be prepared in advance and baked fresh when ready to serve.
- Prep Time: 20 minutes
- Cook Time: 45 minutes
- Total Time: 1 hour 5 minutes (plus chilling time if prepared ahead)
- Yield: 8 servings 1x
- Category: Breakfast
- Method: Baking
- Cuisine: American
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 dish: Grease a 9×13-inch or any 3–4-quart oven-safe dish. Arrange the bread cubes in an even layer at the bottom of the pan to form the casserole base.
- Cook sausage and vegetables: Heat olive oil in a large skillet over medium heat. Add the ground pork sausage and rosemary or Italian seasoning if using. Break the sausage into bite-sized pieces as it cooks. Once it starts to brown, add the chopped onions, minced garlic, chopped bell peppers, sliced mushrooms, and chopped spinach. Cook for about 5 to 6 minutes until the vegetables soften slightly and the sausage is mostly cooked.
- Layer sausage mixture: Remove the skillet from heat and evenly spread the sausage and vegetable mixture over the bread cubes in the baking dish.
- Mix eggs and pour: In a large bowl, whisk together the eggs, salt, black pepper, milk or half-and-half, and shredded cheddar cheese until combined. Pour this mixture evenly over the sausage and bread layer. Optionally, sprinkle a little extra salt and pepper on top.
- Chill the casserole: Cover the casserole with plastic wrap or aluminum foil and refrigerate for a minimum of 30 minutes and up to 24 hours. When ready to bake, let the casserole sit at room temperature for 10 to 15 minutes while the oven preheats.
- Bake the casserole: Preheat the oven to 375°F (191°C). Remove the cover and bake the casserole uncovered for 40 to 45 minutes, until the top is golden brown, edges are crisp, and a toothpick inserted in the center comes out clean.
- Cool and serve: Allow the casserole to cool for about 10 minutes before slicing. Garnish with green onions or parsley if desired, then serve warm.
- Storage and reheating: Leftovers can be stored in the refrigerator for up to 5 days. Reheat individual portions in the microwave to your liking.
Notes
- You can substitute the pork sausage with turkey or chicken sausage for a leaner option.
- Feel free to add or swap vegetables based on preference, such as zucchini or tomatoes.
- Use whole milk, half-and-half, or a dairy-free milk alternative depending on dietary needs.
- The casserole can be prepared up to 24 hours in advance and baked fresh for convenience.
- Make sure the casserole sits at room temperature before baking to ensure even cooking.
- To make this recipe vegetarian, omit the sausage and increase vegetables or add a plant-based sausage alternative.
Keywords: make-ahead breakfast casserole, sausage breakfast casserole, easy breakfast bake, savory custard casserole, baked egg casserole
