Breakfast Casserole Recipe

Your Foolproof Recipe for Holiday and Weekend Mornings

There are few dishes that evoke the same sense of comfort and nostalgia as a classic breakfast casserole. It's the warm hug in a dish waiting for you on a chilly holiday morning, the savory centerpiece of a bustling family brunch, and the taste of lazy, cherished weekends spent with loved ones. It’s a meal that feels both special and effortlessly simple.

This recipe is the culmination of everything we love about this breakfast staple, perfected into one foolproof guide. Its true magic lies in its make-ahead convenience, crowd-pleasing flavor, and a simple method that guarantees a delicious, golden-brown result every single time. Prepare to make your mornings infinitely more relaxed and delicious.

Why Make This Delicious Recipe & When to Serve It

The number one reason to fall in love with this recipe is its incredible convenience. You do all the work the night before—browning the sausage, whisking the eggs, and assembling everything in the dish. In the morning, your kitchen is already clean, and all you have to do is pop it in the oven while you sip your coffee and enjoy the morning.

It's also a guaranteed crowd-pleaser. The hearty combination of savory sausage, fluffy eggs, custardy bread, and gooey melted cheese is a classic for a reason. It satisfies everyone from picky toddlers to hungry adults, making it the perfect single-dish solution for feeding a group.

While this recipe is perfect as written, it’s also an incredibly versatile base. Think of it as a canvas for your culinary creativity, allowing you to incorporate leftover vegetables or different cheeses to make it uniquely your own.

This casserole shines on so many occasions:

Holiday Mornings: An absolute must for a stress-free Christmas, Easter, or Thanksgiving breakfast.
Weekend Brunches: The perfect centerpiece when hosting family or friends for a leisurely weekend meal.
Family Gatherings: Easy to make for a large group and travels well for potlucks or family events.
Weekly Meal Prep: Bake one on Sunday, and you’ll have grab-and-go savory breakfasts for the busy week ahead.

Basic Ingredients (Serves 8-10)

The specific ratio of ingredients is key to achieving the perfect custardy, yet structured, final product.

1 lb Pork Breakfast Sausage: This is the savory, hearty foundation of the casserole. Using bulk sausage (casings removed) makes it easy to crumble and ensures flavorful bits throughout every single bite.
6 Slices Hearty White Sandwich Bread: This is the crucial absorbent layer that creates the casserole’s structure. Using a sturdier, day-old, or lightly toasted bread prevents sogginess and results in a wonderful, custardy texture.
12 Large Eggs: As the star of the show, the eggs bind the casserole together into a rich, stable custard. Using a full dozen ensures the casserole is substantial and won't deflate after baking.
2 Cups Half-and-Half: This is the secret to an ultra-creamy, luxurious custard. It provides a richer texture and more stable set than milk alone, preventing a watery result and elevating the entire dish.
2 Tsp Dry Mustard: This is the hidden flavor powerhouse that makes all the difference. It doesn't make the casserole taste like mustard; instead, it sharpens the cheese flavor and adds a subtle, tangy depth to balance the richness.
8 oz Sharp Cheddar Cheese (2 cups, shredded): This provides the classic, tangy, cheesy goodness we all crave. For the best, smoothest melt, shredding your own cheese from a block is highly recommended, but pre-shredded works in a pinch.
1 ½ Tsp Kosher Salt & ½ Tsp Freshly Ground Black Pepper: These essential seasonings awaken all the other flavors in the dish. Be sure to use them to properly season the egg custard, adjusting the salt slightly based on your sausage.
1 Tbsp Olive Oil: A small amount of olive oil is used for browning the sausage. It prevents the meat from sticking to the pan and helps develop a flavorful crust on the crumbles, adding more depth to the final dish.

Step-by-Step Preparation

Brown the Sausage: In a large skillet, heat the 1 tablespoon of olive oil over medium-high heat until it shimmers. Add the 1 lb of pork breakfast sausage and use a wooden spoon to break it into small crumbles as it cooks. Continue cooking until the sausage is browned and no longer pink, which should take about 5 to 7 minutes. Use a slotted spoon to transfer the cooked sausage to a paper towel-lined plate to drain any excess grease.
Prepare the Custard Base: In a large mixing bowl, crack the 12 large eggs and whisk them vigorously until the yolks and whites are completely combined and uniform in color. Pour in the 2 cups of half-and-half, then add the 2 teaspoons of dry mustard, 1 ½ teaspoons of kosher salt, and ½ teaspoon of black pepper. Whisk everything together until the mixture is smooth and slightly frothy, which helps create a lighter, fluffier final texture.
Combine the Core Components: To the bowl with the egg custard, add the 6 slices of cubed bread, all of the cooked sausage crumbles, and half of the shredded cheddar cheese (that’s 1 cup). Using a large spatula, gently fold all the ingredients together until the bread cubes are evenly moistened and everything is well-distributed. This step ensures every single bite will have the perfect mix of bread, sausage, and cheese.
Assemble the Casserole: Lightly grease a 9x13-inch baking dish with non-stick cooking spray or butter to prevent sticking. Pour the entire sausage and bread mixture from the bowl into the prepared dish, spreading it out into an even layer. Sprinkle the remaining 1 cup of shredded cheddar cheese evenly over the top, which will bake into a beautiful, golden-brown cheesy crust.
Chill Overnight (The Make-Ahead Step): Cover the dish tightly with aluminum foil and place it in the refrigerator for at least 8 hours or up to 24 hours. This crucial resting period allows the bread to fully absorb the rich custard, which is the secret to achieving a perfect, non-soggy texture and deeply melded flavors. For the absolute best results, do not skip this step.
Bake to Golden Perfection: The next morning, preheat your oven to 350°F (175°C) and let the casserole sit at room temperature while the oven heats. Bake the casserole, still covered with foil, for 30 minutes. Then, carefully remove the foil and continue baking for another 20 to 25 minutes. The casserole is done when the center is set (a knife inserted into the middle comes out clean) and the top is bubbly and beautifully golden brown.
Rest Before Serving: Remove the casserole from the oven and let it rest on a cooling rack for at least 10 minutes before slicing. This important step allows the egg custard to finish setting up, ensuring you can cut clean, beautiful squares that hold their shape perfectly. It will be tempting to dig in right away, but your patience will be rewarded with perfect slices.

Tips for the Perfect Recipe

Bread is Key
- Stale is Great: Day-old or slightly stale bread is your best friend for this recipe. It has less moisture, allowing it to soak up the egg custard like a sponge without turning to mush and falling apart.
- No Stale Bread? No Problem: If you only have fresh bread, you can easily dry it out. Simply cube the slices and toast them in a 350°F oven for about 10 minutes, or just leave them out on the counter for a few hours before using.
Achieve Ultimate Creaminess
- Richer Dairy: Using half-and-half, as this recipe calls for, creates a noticeably richer and more stable custard than using milk alone. For an even more decadent texture with a slight tang, you can substitute ½ cup of the half-and-half with full-fat sour cream.
- Shred Your Own Cheese: Bags of pre-shredded cheese are convenient, but they are often coated with starches that can prevent them from melting as smoothly. For the gooiest, most satisfying cheese pull, buy a block of sharp cheddar and shred it yourself just before using.
Master Moisture Control
- Pre-cook Your Fillings: Always cook your sausage and drain the excess fat as directed in the recipe. If you decide to add vegetables with high water content—like mushrooms, onions, or spinach—it is essential to sauté them first to release their moisture before adding them to the casserole. This is the single most important rule to prevent a watery, disappointing result.
Don't Compress
- Gentle Mixing: When you combine the bread with the liquid custard, fold gently with a spatula. Over-mixing or stirring too vigorously can cause the bread to break down and disintegrate into a uniform mush. You want to see distinct, custardy cubes of bread in the final dish.

Serving Ideas

Fresh Garnishes: A sprinkle of fresh herbs provides a lovely pop of color and flavor that cuts through the richness of the casserole.
- Chopped Chives or Green Onions: Add a mild, fresh oniony bite that complements the sausage and cheese perfectly.
- Fresh Parsley: Provides a clean, bright, and herbaceous note.
Cool and Creamy Toppings: Offer these on the side for a delightful contrast in temperature and texture.
- Sliced Avocado: The creaminess and healthy fats are a perfect counterpoint to the savory casserole.
- A Dollop of Sour Cream: Adds a cool, refreshing tanginess that brightens up each bite.
Sauces on the Side: Allow guests to customize their slice with a selection of sauces.
- Your Favorite Hot Sauce: A few dashes are perfect for those who enjoy a little spicy kick with their eggs.
- Fresh Salsa or Pico de Gallo: Adds a zesty, juicy, and fresh element that lifts the entire dish.
Simple Side Dishes: Balance the hearty casserole with something light and fresh.
- Fresh Fruit Salad: A simple mix of melon, berries, and citrus provides a sweet and refreshing contrast.
- A Simple Green Salad: A handful of arugula or mixed greens tossed in a light lemon vinaigrette can easily turn this breakfast into a wonderful brunch or lunch meal.

Tips for Storing and Reheating

Storing Leftovers

Refrigeration: Once the casserole has cooled completely to room temperature, cover the dish tightly with aluminum foil or transfer individual slices to an airtight container. It will keep well in the refrigerator for up to 4 days.
Freezing a Baked Casserole: For longer storage, let the casserole cool completely. You can freeze the entire dish by wrapping it tightly first in plastic wrap, then in a layer of aluminum foil, for up to 2 months. For easier portions, cut the cooled casserole into individual squares, wrap each one securely, and store them together in a large freezer-safe bag.
Freezing an Unbaked Casserole: This is a fantastic option for ultimate make-ahead convenience. Assemble the casserole completely in a freezer-safe dish, but do not bake it. Cover it tightly with both plastic wrap and foil to prevent freezer burn, and freeze for up to 3 months.

Reheating Tips

From the Refrigerator (Oven Method): The oven is the best method for reheating multiple servings and achieving a just-baked texture. Place the casserole (or slices) in an oven-safe dish, cover loosely with foil to prevent drying out, and reheat at 325°F (165°C) for 20-30 minutes, or until warmed through. The internal temperature should reach 165°F.
From the Refrigerator (Microwave Method): For a single slice, the microwave is the fastest option. Place the slice on a microwave-safe plate, cover it loosely to prevent splatters, and heat for 60-90 seconds, or until hot. Using 50% power for a longer duration can help it heat more evenly and gently.
From Frozen: For best results, thaw the casserole (whether baked or unbaked) in the refrigerator overnight. Then, bake or reheat according to the directions above. You may need to add 10-20 minutes to the baking time if it's still very cold from the fridge.

Conclusion

This breakfast casserole is more than just a recipe; it’s a reliable strategy for creating delicious, stress-free mornings filled with warmth, comfort, and connection. With its rich savory flavors, perfectly custardy texture, and foolproof make-ahead method, it’s destined to become a treasured tradition on your family’s table for holidays and lazy weekends alike.

Frequently Asked Questions

Q: Can I bake this casserole the same day I assemble it?

A: Yes, you absolutely can! While the overnight chill is recommended for the best texture, you can bake it right away. Just let the assembled casserole rest at room temperature for at least 30-60 minutes before baking to give the bread some time to absorb the egg mixture.

Q: What are the best substitutions if I don't have sausage or cheddar?

A: This recipe is very forgiving! You can easily swap the 1 lb of pork sausage for cooked and crumbled bacon, diced ham, or a plant-based sausage. For the cheese, any good melting cheese like Monterey Jack, Gruyère, or Pepper Jack (for a kick!) will work wonderfully in place of the cheddar.

Q: My last breakfast casserole was watery. How do I prevent that with this recipe?

A: A watery casserole is almost always due to excess moisture from fillings. To prevent this, always pre-cook any vegetables you add, especially mushrooms, onions, or spinach, to release their water before adding them to the egg mixture. This recipe is designed to be rich and stable, but managing moisture from add-ins is key.

Q: How can I make this recipe gluten-free?

A: Making a gluten-free version is simple. Just substitute the 6 slices of white bread with an equal amount of your favorite gluten-free sandwich bread. Since gluten-free breads vary, choose one with a softer texture that can absorb the egg custard well. The other ingredients are naturally gluten-free, but always check your sausage label to be certain.