Overnight Sausage and Egg Breakfast Casserole

Bianca

Founder of Red Recipe

This post may contain affiliate links learn more.

My family mornings are usually a whirlwind of getting everyone ready for school and work, often leaving little time for a proper, sit-down breakfast. That’s why discovering the Overnight Sausage and Egg Breakfast Casserole was a game-changer! This recipe has become a beloved weekend tradition and a lifesaver for busy holiday mornings. The beauty of it is the prep-ahead magic; you assemble it the night before, and in the morning, you just pop it in the oven. The aroma that fills the kitchen as it bakes is simply irresistible, and the taste? Imagine savory sausage, fluffy eggs, melted cheese, and slightly crisp bread all baked to golden perfection. Even my pickiest eaters devour it, and I always get requests for seconds – and thirds! If you’re looking for a stress-free, crowd-pleasing breakfast or brunch option, look no further. This Overnight Sausage and Egg Breakfast Casserole is guaranteed to become a staple in your kitchen, just like it has in mine.

Ingredients

Breakfast Sausage: 1 pound, adds savory flavor and hearty protein. Choose your favorite type – mild, hot, or Italian sausage all work wonderfully.
Eggs: 12 large, the base of the casserole, providing richness and structure. Use fresh, large eggs for the best texture and volume.
Bread: 6 cups cubed, day-old bread works best, absorbing the egg mixture without becoming soggy. Use your favorite type – French bread, sourdough, or even challah are great options.
Milk: 2 cups, adds moisture and creaminess to the egg mixture. Whole milk is recommended for richness, but 2% or even non-dairy milk can be substituted.
Heavy Cream: 1 cup, enhances the richness and creates a luxurious texture. Can be substituted with half-and-half for a slightly lighter version.
Shredded Cheese: 2 cups, provides cheesy goodness and melty texture. Cheddar, Monterey Jack, mozzarella, or a blend are all delicious choices.
Onion: 1 medium, diced, adds a subtle savory flavor and aromatic depth to the casserole. Yellow or white onion works best.
Green Bell Pepper: 1 medium, diced, contributes a mild, slightly sweet flavor and a touch of color. Red or orange bell pepper can also be used.
Garlic: 2 cloves, minced, enhances the savory flavors of the sausage and vegetables. Freshly minced garlic is recommended for the best flavor.
Dijon Mustard: 1 tablespoon, adds a tangy depth of flavor that complements the sausage and cheese.
Salt: 1 teaspoon, enhances all the flavors in the casserole. Adjust to taste.
Black Pepper: ½ teaspoon, adds a touch of spice and balances the richness. Adjust to taste.
Fresh Parsley: 2 tablespoons, chopped (optional), adds a fresh, herbaceous garnish and a pop of color.

Instructions

Prepare the Sausage and Vegetables: Begin by browning the breakfast sausage in a large skillet over medium heat. As the sausage cooks, break it apart with a spoon or spatula into smaller crumbles. Continue cooking until the sausage is fully cooked and no longer pink. Drain off any excess grease from the skillet. This step is crucial for ensuring the sausage is cooked through and not greasy in the final casserole.
Sauté Aromatics: Add the diced onion and green bell pepper to the skillet with the cooked sausage. Sauté the vegetables over medium heat for about 5-7 minutes, or until they soften and the onion becomes translucent. Stir in the minced garlic during the last minute of sautéing, cooking until fragrant. Be careful not to burn the garlic, as it can become bitter. Sautéing the vegetables beforehand helps to release their flavors and ensures they are tender in the baked casserole.
Whisk the Egg Mixture: In a large bowl, whisk together the eggs, milk, heavy cream, Dijon mustard, salt, and black pepper until well combined and slightly frothy. Whisking thoroughly ensures a smooth and even texture for the egg mixture, which will result in a fluffier casserole. The Dijon mustard adds a subtle tang that balances the richness of the eggs and cheese.
Assemble the Casserole: Grease a 9×13 inch baking dish with cooking spray or butter. Spread the cubed bread evenly in the bottom of the prepared baking dish. Layer the cooked sausage and vegetable mixture over the bread. Sprinkle the shredded cheese evenly over the sausage and vegetables. Pour the egg mixture over the entire casserole, ensuring that it evenly saturates the bread and other ingredients. Gently press down on the bread with a spatula or spoon to help it absorb the egg mixture.
Refrigerate Overnight (or at least 2 hours): Cover the baking dish tightly with plastic wrap or aluminum foil. Refrigerate the casserole for at least 2 hours, or preferably overnight, for the flavors to meld and the bread to fully absorb the egg mixture. This overnight chilling is what makes this recipe so convenient for make-ahead breakfasts or brunches. The longer chilling time also contributes to a more cohesive and flavorful casserole.
Preheat Oven and Bake: In the morning, preheat your oven to 350°F (175°C). Remove the casserole from the refrigerator and let it sit at room temperature for about 15-20 minutes while the oven preheats. This helps to prevent the baking dish from cracking due to a sudden temperature change.
Bake the Casserole: Bake the casserole, uncovered, for 45-55 minutes, or until it is golden brown and set in the center. To check for doneness, insert a knife into the center of the casserole; it should come out clean. The top should be nicely browned, and the edges should be slightly crisp. If the top is browning too quickly, you can loosely tent it with aluminum foil for the last 15-20 minutes of baking.
Rest and Serve: Once baked, remove the casserole from the oven and let it rest for 5-10 minutes before slicing and serving. This resting time allows the casserole to set up further and makes it easier to slice and serve neatly. Garnish with fresh parsley, if desired, for a pop of color and fresh flavor. Serve warm and enjoy!

Nutrition Facts (per serving, approximate)

Serving Size: 1 slice (approximately 1/8 of the casserole)
Calories: 450 kcal
Protein: 25g

Please note: Nutrition facts are estimates and can vary based on specific ingredients and portion sizes.

Preparation Time

Prep Time: 30 minutes (active preparation, including cooking sausage, sautéing vegetables, and assembling the casserole)
Chill Time: Overnight (minimum 2 hours, recommended overnight for best results)
Cook Time: 45-55 minutes (baking time in the oven)
Total Time (excluding chill time): Approximately 1 hour 15 minutes

This Overnight Sausage and Egg Breakfast Casserole is incredibly convenient because the majority of the work is done the day before. The morning of, it’s just a matter of baking it to golden perfection, making it perfect for busy mornings or when you’re hosting brunch.

How to Serve

This versatile breakfast casserole can be served in numerous ways to complement your meal and suit different occasions. Here are some ideas:

As a Standalone Main Dish: This casserole is hearty enough to be the star of your breakfast or brunch. Serve it warm, sliced into squares, and enjoy it as is.
With Fresh Fruit: Balance the richness of the casserole with a side of fresh fruit. Berries (strawberries, blueberries, raspberries), melon (cantaloupe, watermelon), or sliced oranges provide a refreshing contrast.
With a Simple Salad: A light and fresh green salad with a vinaigrette dressing can cut through the richness of the casserole and add a healthy element to your meal.
With Yogurt and Granola: Offer a side of plain or Greek yogurt with granola for those who prefer a lighter accompaniment or want to add a bit of sweetness and crunch.
With Hot Sauce or Salsa: For those who like a bit of spice, serve the casserole with hot sauce, salsa, or pico de gallo. These add a zesty kick and enhance the savory flavors.
With Toast or Biscuits: If you want to make the meal even heartier, serve the casserole with toasted bread, English muffins, or biscuits on the side for dipping and scooping.
For Brunch Buffets: This casserole is perfect for brunch buffets or potlucks. It’s easy to transport and serve, and it can be made ahead of time, freeing up your morning.
For Holiday Mornings: Make your holiday mornings less stressful by preparing this casserole the night before. It’s a crowd-pleasing and festive option for Christmas, Easter, or Thanksgiving brunch.
For Weekday Breakfast (Make Ahead): While it’s called “Overnight,” you can bake this casserole and store leftovers in the refrigerator. Reheat individual slices for a quick and satisfying weekday breakfast.

Additional Tips

Use Day-Old Bread: Day-old bread is ideal for casseroles because it’s slightly drier and absorbs the egg mixture better without becoming mushy. If you only have fresh bread, you can lightly toast it in the oven to dry it out a bit before cubing.
Customize Your Cheese: Feel free to experiment with different types of cheese to customize the flavor profile. Pepper jack for a spicy kick, Gruyere for a nutty and complex flavor, or a blend of cheddar and mozzarella for a classic cheesy taste are all great options.
Add More Vegetables: Don’t hesitate to add other vegetables to your casserole. Mushrooms, spinach, diced tomatoes, or roasted red peppers would all be delicious additions. Sauté any extra vegetables alongside the onions and peppers.
Spice it Up: If you like a spicier casserole, use hot breakfast sausage, add a pinch of red pepper flakes to the egg mixture, or include some chopped jalapeños with the vegetables.
Make it Vegetarian: For a vegetarian version, substitute the sausage with plant-based breakfast sausage crumbles or add more vegetables like roasted vegetables (broccoli, cauliflower, carrots) or sautéed mushrooms and spinach.
Ensure Even Baking: To ensure even baking, make sure the egg mixture is evenly distributed throughout the casserole. Gently press down on the bread to submerge it in the liquid. If your oven tends to bake unevenly, rotate the casserole halfway through baking.
Don’t Overbake: Overbaking can make the eggs dry and rubbery. Bake until the casserole is set in the center and golden brown, but still slightly moist. The carryover cooking will finish setting it as it rests.
Freezing for Later: While best fresh, you can freeze leftover casserole. Let it cool completely, then cut it into individual portions, wrap tightly in plastic wrap and then foil, and freeze. Thaw overnight in the refrigerator and reheat in the oven or microwave until heated through.

FAQ Section

Q1: Can I make this casserole the same day instead of overnight?
A: Yes, you can! While the overnight chill allows the flavors to meld and the bread to absorb the egg mixture best, you can bake it after chilling for at least 2 hours. If baking the same day, ensure you let it chill for at least 2 hours in the refrigerator before baking to allow the bread to soak up the egg mixture.

Q2: Can I use a different type of bread?
A: Absolutely! French bread, sourdough, Italian bread, challah, or even croissants all work well in this casserole. Choose a bread that is sturdy enough to hold its shape and absorb the egg mixture without falling apart. Avoid very soft breads like sandwich bread, which can become too soggy.

Q3: What if I don’t have heavy cream? Can I substitute it?
A: Yes, you can substitute heavy cream with half-and-half or even whole milk for a lighter casserole. Using half-and-half will still provide a creamy texture, though slightly less rich than heavy cream. Whole milk will result in a less rich but still delicious casserole.

Q4: Can I add different types of meat besides sausage?
A: Certainly! You can use cooked and crumbled bacon, ham, or even cooked chorizo in place of or in addition to the sausage. Just ensure any meat you use is pre-cooked before adding it to the casserole.

Q5: How do I store leftover breakfast casserole?
A: Store leftover breakfast casserole in an airtight container in the refrigerator for up to 3-4 days. Reheat individual slices in the microwave or in the oven until heated through.

Q6: Can I double the recipe for a larger crowd?
A: Yes, this recipe can easily be doubled to serve a larger group. Simply double all the ingredients and use a larger 9×13 inch baking dish (or two 9×13 inch dishes if your oven space is limited). Baking time may need to be slightly increased, so check for doneness around 50 minutes and add more time if needed.

Q7: My casserole is browning too quickly on top, what should I do?
A: If your casserole is browning too quickly on top before the center is set, loosely tent it with aluminum foil. This will help to prevent the top from burning while allowing the inside to continue cooking through.

Q8: Can I add a topping to the casserole before baking?
A: Yes, you can add a topping for extra flavor and texture! Consider topping the casserole with extra shredded cheese, crispy fried onions, or a sprinkle of breadcrumbs before baking. These toppings will add a nice finishing touch and extra crunch to your breakfast casserole.