Easy Make-Ahead Breakfast Casserole with Sausage, Vegetables, and Cheddar Recipe

Introduction

This easy make-ahead breakfast casserole is a hearty and flavorful start to any morning. Loaded with sausage, vegetables, and cheese, it can be prepared the night before and baked fresh when you’re ready to eat. Perfect for busy weekdays or weekend brunches.

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 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
• 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

1. Step 1: 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.
2. Step 2: Heat olive oil in a large skillet over medium heat. Add the sausage and rosemary or Italian seasoning, if using. Break up the sausage into bite-sized pieces as it cooks.
3. Step 3: Add the chopped onion, minced garlic, bell peppers, mushrooms, and spinach to the skillet. Cook until the vegetables have softened slightly and the sausage is mostly cooked through, about 5–6 minutes.
4. Step 4: Remove the sausage and vegetable mixture from heat and spread it evenly over the bread cubes in the baking dish.
5. Step 5: In a large bowl, whisk together the eggs, salt, pepper, milk or half-and-half, and shredded cheddar cheese. Pour the egg mixture evenly over the sausage and vegetables. Sprinkle a little extra salt and pepper on top.
6. Step 6: Cover the casserole with plastic wrap or aluminum foil. Refrigerate for at least 30 minutes and up to 24 hours. When ready to bake, let it sit at room temperature for 10–15 minutes while preheating the oven.
7. Step 7: Preheat the oven to 375°F (191°C). Bake the casserole uncovered until the top is golden, the edges are crisp, and a toothpick inserted in the center comes out clean, about 40–45 minutes.
8. Step 8: Allow the casserole to cool for 10 minutes before slicing. Garnish with green onion or parsley if desired and serve.

Tips & Variations

• Use whole wheat or sourdough bread for extra flavor and texture.
• Swap pork sausage for turkey sausage or a vegetarian alternative for a lighter version.
• Add your favorite vegetables like zucchini or tomatoes to customize the filling.
• For extra creaminess, mix in a little cream cheese or mozzarella along with the cheddar.

Storage

Store any leftover casserole covered in the refrigerator for up to 5 days. Reheat individual portions in the microwave until warmed through, or reheat the whole casserole in the oven at 350°F (175°C) until heated evenly.

How to Serve

Serve this delicious recipe with your favorite sides.

FAQs

Can I prepare this casserole entirely the night before?

Yes, you can assemble the casserole the night before and refrigerate it until ready to bake. Just be sure to let it sit at room temperature for 10–15 minutes before putting it in the oven.

Can I freeze this breakfast casserole?

Yes, you can freeze the casserole before baking. Cover it tightly with plastic wrap and foil, then freeze for up to 2 months. Thaw overnight in the refrigerator before baking as directed.

Easy Make-Ahead Breakfast Casserole with Sausage, Vegetables, and Cheddar Recipe

Print Recipe

★★★★★

4.8 from 147 reviews

This easy make-ahead breakfast casserole combines crusty bread cubes with a savory mixture of sausage, vegetables, eggs, and cheese. Prepared the night before and baked in the morning, it’s perfect for busy mornings or brunch gatherings, delivering a flavorful, comforting dish everyone will love.

• Author: Dana
• Prep Time: 20 minutes
• Cook Time: 45 minutes
• Total Time: 1 hour 5 minutes plus refrigeration time
• Yield: 8 servings 1x
• Category: Breakfast Casserole
• Method: Baking
• Cuisine: American

Ingredients

Scale 1x2x3x

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

1. Prepare the baking dish: Grease a 9×13-inch or any 3–4-quart oven-safe dish. Arrange the crusty bread cubes in an even layer on the bottom of the pan to form the base of the casserole.
2. Cook sausage and vegetables: Heat olive oil in a large skillet over medium heat. Add the ground sausage and optional dried rosemary or Italian seasoning. Break up the sausage into bite-sized pieces with a wooden spoon or rubber spatula as it cooks. Then add the chopped onion, minced garlic, chopped bell peppers, sliced mushrooms, and fresh spinach. Cook everything together until the vegetables are slightly softened and the sausage is mostly cooked through, about 5 to 6 minutes.
3. Layer sausage mixture: Remove the sausage and vegetable mixture from heat and spread it evenly over the bread cubes in the prepared baking dish.
4. Mix eggs and dairy: In a large bowl, whisk together the 12 large eggs, salt, freshly ground black pepper, milk or half-and-half, and shredded cheddar cheese. Pour this egg mixture evenly over the sausage and vegetable layer in the baking dish. Sprinkle a little extra salt and pepper on top for added seasoning.
5. Refrigerate the casserole: Cover the casserole with plastic wrap or aluminum foil and refrigerate for at least 30 minutes and up to 24 hours. This allows the bread to soak up the egg mixture fully. Before baking, let the casserole sit at room temperature for 10 to 15 minutes while preheating the oven.
6. Bake: Preheat your oven to 375°F (191°C). Bake the casserole uncovered until the top is golden, the edges are crisp, and a toothpick inserted into the center comes out clean. This will take approximately 40 to 45 minutes.
7. Cool and serve: Remove the casserole from the oven and let it cool for about 10 minutes. Slice into portions and serve. Garnish with green onions or chopped parsley if desired.
8. Storage and reheating: Store any leftovers in the refrigerator for up to 5 days. Reheat individual portions in the microwave to your liking.

Notes

• Using crusty bread such as French or sourdough works best to absorb the egg mixture without becoming soggy.
• Ground pork sausage can be substituted with ground turkey or chicken for a leaner option.
• Feel free to swap or add vegetables such as zucchini, tomatoes, or kale based on preference.
• Milk can be substituted with half-and-half or a non-dairy milk like almond milk for creaminess.
• For extra flavor, sprinkle additional cheese on top during the last 5 minutes of baking to create a golden crust.
• This casserole can be prepared entirely the night before for convenience.

Keywords: make-ahead breakfast casserole, sausage breakfast bake, savory egg casserole, easy brunch recipe