Best Make Ahead Breakfast Casserole Recipe (Easy!)

Imagine waking up on a holiday morning or a busy weekend, knowing that a delicious and hearty breakfast is already prepped and waiting to be baked. This Make Ahead Breakfast Casserole Recipe is your answer to stress-free mornings and satisfied appetites. It’s packed with savory sausage, colorful vegetables, and plenty of cheese, all nestled in a bed of crusty bread soaked in a rich egg custard. This recipe is incredibly easy to throw together the night before, leaving you with nothing but a simple bake in the morning.

Why You’ll Love This Recipe

This isn’t just another breakfast casserole. My recipe has a secret ingredient that elevates it far beyond the ordinary.

Blooming Herbs: The unique twist in this recipe is blooming dried herbs in melted butter before adding the sausage and vegetables. This simple step unlocks the full potential of the herbs, infusing the entire casserole with a deeper, more complex flavor.

To understand more about how herbs infuse flavor, you can read about the safe handling of spices and herbs on the USDA website.

Make-Ahead Convenience: Perfect for busy mornings, holidays like Easter, Thanksgiving, or Christmas, or any weekend brunch, this casserole can be assembled the night before, saving you precious time and effort. Wake up, preheat the oven, and bake! If you’re looking for more inspiration for Easter, you might like these easy Easter dessert recipes.

Crowd-Pleasing: This breakfast casserole is always a hit with family and friends. It’s hearty, flavorful, and satisfying, making it the perfect centerpiece for any gathering.

Easy to Customize: Adaptable to different tastes and dietary needs, this recipe can be easily modified with your favorite vegetables, cheeses, or protein sources. I’ll give you some tips on easy substitutions.

Ingredients Needed

Here are the ingredients you’ll need to create this amazing breakfast casserole:

• 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

Ingredient Notes & Substitutions

Bread: Sourdough or Italian bread works wonderfully. Stale bread is actually preferred as it soaks up the egg mixture without becoming soggy. You can also use gluten-free bread to make it gluten-free.

Sausage: Feel free to experiment with different types of sausage, such as Italian sausage, turkey sausage, or even chorizo. For a vegetarian option, use plant-based sausage crumbles.

Milk/Half-and-Half: Half-and-half adds a richer flavor, but you can easily substitute with milk or a dairy-free alternative like almond milk or oat milk.

Cheese: I love using sharp cheddar cheese for its bold flavor, but Monterey Jack, Gruyere, or Pepper Jack are also delicious options.

How to Make Make Ahead Breakfast Casserole Recipe

Follow these simple steps to create a breakfast casserole that will impress everyone.

Step 1: Prepare the Baking Dish

Grease a 9×13-inch or any 3–4-quart oven-safe dish. Arrange bread cubes in an even layer in bottom of pan. The bread should cover the bottom of the dish evenly.

Step 2: Cook the Sausage and Vegetables

Heat olive oil in a large skillet over medium heat. Add sausage and rosemary/Italian seasoning, if using. 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. As the herbs bloom in the oil, you’ll notice a delightful aroma. The sausage will sizzle and brown, creating a savory base for the casserole.

Step 3: Layer the Sausage Mixture

Remove sausage and vegetable mixture from heat and spread in an even layer on top of bread. Make sure the sausage mixture is evenly distributed over the bread.

Step 4: Add the Egg Mixture

Whisk the eggs, salt, pepper, milk, and cheese together. Evenly pour over sausage/vegetable mixture. Add another sprinkle of salt and pepper on top. The egg mixture should cover all the bread and sausage.

Step 5: Refrigerate

Cover casserole with plastic wrap or aluminum foil and refrigerate for at least 30 minutes and up to 24 hours. This step is important because refrigerating helps the flavors meld together and ensures the bread has time to soak up the egg mixture. When ready to bake, allow to sit at room temperature for 10–15 minutes as oven preheats.

Step 6: Bake

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. The top will turn a beautiful golden brown, and you’ll see bubbling around the edges. The toothpick test ensures it’s cooked through.

Step 7: Cool and Serve

Cool for 10 minutes, then slice and serve. Letting it cool slightly makes slicing much easier and prevents the casserole from falling apart.

Step 8: Store Leftovers

Leftovers keep well in the refrigerator for up to 5 days. Reheat in the microwave to your liking.

Preventing a Soggy Casserole

Nobody likes a soggy breakfast casserole! Here’s how to avoid it:

The science behind sogginess is that too much moisture and not enough binding occurs. Using the right bread is important.

Use Stale Bread: This is the most important tip! Stale or slightly dried-out bread absorbs the egg mixture without becoming mushy.

Don’t Overcrowd the Pan: Overcrowding traps moisture, preventing the casserole from cooking evenly.

Cook Vegetables First: Sautéing the vegetables before adding them to the casserole helps to evaporate excess moisture.

Consider a Bread Crumb Layer: A thin layer of bread crumbs on the bottom of the dish can absorb excess moisture.

Pro Tips & Troubleshooting

Pro Tips

Bloom the Herbs: Don’t skip this step! Blooming the dried herbs in olive oil releases their essential oils, resulting in a more flavorful casserole.

Use High-Quality Sausage: The better the sausage, the better the casserole! Choose a flavorful sausage that you enjoy.

Don’t Overbake: Overbaking can lead to a dry and rubbery casserole. Keep an eye on it and use the toothpick test.

Let it Rest: Letting the casserole rest for 10 minutes before slicing allows it to set, making it easier to serve.

Add a Crispy Topping: Sprinkle extra cheese or breadcrumbs on top during the last few minutes of baking for added texture.

Make it Ahead: Prep all the ingredients the day before for quick assembly in the morning.

Common Mistakes to Avoid

Using Fresh Bread: Fresh bread will result in a soggy casserole.

Adding Too Many Wet Ingredients: Be mindful of the amount of milk and vegetables you add.

Skipping the Refrigeration Step: Refrigerating the casserole allows the flavors to meld and the bread to absorb the egg mixture.

Not Cooking Vegetables Properly: Undercooked vegetables can release moisture during baking.

Overbaking the Casserole: This results in a dry and rubbery texture.

Serving & Storage

Serving Ideas

This breakfast casserole is delicious on its own, but here are a few serving suggestions:

Side Dishes: Serve with fresh fruit, yogurt, or a light side salad.

Garnishes: Garnish with fresh green onion, chopped parsley, or everything bagel seasoning.

Breakfast Sauces: Offer hot sauce, salsa, or pico de gallo for an extra kick.

Drinks: Pair with coffee, orange juice, or mimosas.

Storage and Make-Ahead

Refrigeration: Store leftovers in an airtight container in the refrigerator for up to 5 days.

Freezing: You can freeze the unbaked casserole for up to 3 months. Thaw overnight in the refrigerator before baking as directed. You can also freeze baked casserole in slices.

Reheating: Reheat in the microwave or oven until warmed through.

Make-Ahead: Assemble the casserole the night before and store it in the refrigerator. Bake as directed in the morning.

Conclusion

This Make Ahead Breakfast Casserole Recipe is more than just a meal; it’s a stress-free solution to delicious mornings. With its customizable ingredients and simple steps, it’s a perfect choice for holidays, brunches, or any day you want a hearty and flavorful breakfast without the fuss. The blooming herbs add a special touch that will have everyone asking for your secret. Don’t be afraid to experiment with different variations to create your own signature breakfast casserole. Print this recipe and share it with your friends and family!

For additional information on breakfast casseroles, you might find this article on Breakfast Casseroles helpful.

FAQ

Here are some frequently asked questions about this recipe:

How can I ensure my breakfast casserole isn’t soggy? Using stale bread, pre-cooking your vegetables to release excess moisture, and avoiding over-saturation with liquids will help prevent a soggy casserole.

What are the best make-ahead and freezing instructions for this casserole? Assemble the casserole, cover it tightly, and refrigerate for up to 24 hours or freeze for up to 3 months. If frozen, thaw overnight in the refrigerator before baking. Bake as directed.

What are some variations and substitutions I can make (vegetarian, gluten-free, dairy-free)? For a vegetarian version, use plant-based sausage. Use gluten-free bread for a gluten-free option. For dairy-free, substitute almond milk and dairy-free cheese.

What side dishes pair well with this breakfast casserole? Fresh fruit, yogurt, or a light side salad complement this casserole nicely. Consider adding a 7 layer salad to your brunch menu for a complete meal.

How long can I store leftovers, and what is the best way to reheat them? Store leftovers in the refrigerator for up to 5 days. Reheat in the microwave or oven until warmed through.

Can I prepare this ahead of time and what is the best way to store? Yes, you can assemble it the night before and store it in the fridge or freeze it for longer storage.

Can I use frozen vegetables in this casserole? Yes, but thaw and drain them well to remove excess moisture before adding them to the casserole.

What is the best temperature to bake this at? 375°F (191°C) is the optimal temperature for baking this casserole, ensuring even cooking and a golden-brown top.