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This easy Breakfast Casserole recipe layers eggs, sausage, cheese, and day-old bread into one satisfying dish. Each slice is thick, hearty, and delicious, making it one of the best breakfast casseroles for feeding a crowd! Best of all, you can make it ahead of time, so it’s ready to bake fresh on Christmas morning, Easter brunch, or any day!
This is my family’s favorite breakfast casserole. I make it every year for Christmas morning, plus the occasional weekend brunch, and yes, even for dinner. It’s hearty, delicious, and super easy to make with just seven main ingredients. Unlike my Tater Tot Breakfast Casserole, this version uses bread as the base, giving it a lighter, fluffier texture similar to savory bread pudding. Each bite is thick and flavorful, with crispy, golden edges and melty cheese topping.
It’s endlessly versatile, too! You can add your favorite veggies, seasonings, and experiment with different cheeses, like pepper jack or feta. And just like my Biscuits and Gravy Casserole, this easy breakfast casserole can be made ahead of time and baked the next morning. I always recommend serving it it with a yummy fruit salad and bakery-style blueberry muffins for the ultimate breakfast spread.
Table of Contents
Key Ingredients and Substitutions
This breakfast casserole comes together with a handful of everyday ingredients that you can easily customize to suit your family’s taste.
- Olive Oil: Used to sauté the onions and sausage. You can substitute with butter for a richer flavor or avocado oil for a neutral option.
- Onion: Adds sweetness and depth. Yellow onion is the classic choice, but white or red onion can be used. For a milder flavor, try shallots or green onions.
- Ground Sausage: Pork breakfast sausage is most traditional, but you can also use Italian sausage (sweet or hot), chicken sausage, or turkey sausage. If using Italian sausage, note that it will bring additional seasoning to the dish.
- Eggs: The foundation of this casserole. Large eggs work best, but you can swap in Egg Beaters Original (3/4 cup equals 4 large eggs) or plant-based JUST Egg (½ cup equals 2 large eggs) if you prefer an alternative.
- Whole Milk: Gives the casserole a creamy texture without being too heavy. For a richer result, swap in half-and-half or combine whole milk with a splash of heavy cream. For a plant-based alternative, try Silk Nextmilk Whole Fat or Elmhurst Cashew Milk for the closest taste and texture.
- Seasonings (Salt, Black Pepper, Garlic Powder): A simple and classic combination. One reader suggested adding “about a teaspoon or 2 of mustard to this recipe” to make the flavors pop.
- Cheese (Parmesan and Gouda): Parmesan adds a nutty bite, while Gouda melts beautifully for a creamy texture. For best results, shred cheese from the block for the best melt because pre-shredded cheese contains anti-caking agents that may prevent it from melting smoothly. Substitutions include cheddar, mozzarella, Swiss, or pepper jack for a little heat. For a plant-based option, use Violife Just Like Parmesan and Miyoko’s Smoked Gouda which both shred and melt well.
- Day-Old Bread: Day-old bread is bread that has dried slightly, making it better at soaking up the egg and milk mixture without turning mushy. Freshly baked French bread, English muffins, Brioche, challah, or sourdough are all excellent choices. Avoid soft sandwich bread, wheat bread, or very airy white bread because they will not hold up during baking.
How to Make This Easy Breakfast Casserole, Step By Step
See the recipe card below for detailed instructions and the full printable recipe.
- Cook the sausage and onions. Brown the sausage with the diced onion until the meat is fully cooked and the onion is softened.
- Whisk the custard base. Combine the eggs, milk, seasonings, to create a silky mixture that will bind the casserole together (image 1).
- Add cheese and sausage. Stir in the shredded cheeses (image 2) along with the fully cooled sausage and onions.
- Assemble. Layer the cubed day-old bread in a greased 9×13 baking dish and pour the egg mixture evenly over the top (image 3).
- Chill if possible. Cover and refrigerate for at least 1 hour or overnight for the best texture.
- Bake. Bake covered for 35 minutes, then uncover and bake 25 minutes more, or until the edges are golden and the center is set (image 4).
Tips For Making It Ahead Of Time
This breakfast casserole is perfect for holidays and busy mornings because it can be assembled in advance and popped in the oven whenever you’re ready to serve it.
Assemble the night before. Prepare the casserole completely, cover it tightly with foil, and refrigerate overnight. This allows the bread to soak up the custard mixture, resulting in the best texture.
Bake straight from the fridge. The next morning, place the casserole in the oven while it preheats. If it is very cold, expect to add at least 10 to 20 minutes to the baking time.
Freeze before baking. Assemble the casserole, wrap it in plastic wrap and foil, and freeze for up to 3 months. Thaw overnight in the refrigerator, then bake as directed.
Tip: For best results, use day-old bread that is sturdy enough to hold up to the egg mixture.
Easy Variations
This recipe is incredibly flexible, making it easy to adapt to your family’s tastes or whatever ingredients you already have on hand.
- Protein Swaps: Replace the sausage with cubed ham, crispy oven-baked bacon or shredded chicken for a different flavor profile.
- Change the Base: Instead of cubed bread, try English muffins, bagels, croissants, or savory biscuits for a fun twist.
- Add Veggies: Stir in sautéed mushrooms or roasted butternut squash, or add fresh spinach, kale, bell peppers, or tomatoes for extra nutrition and color.
- Try a Different Cheese: Experiment with cheddar, Swiss, feta, goat cheese, Colby Jack, or pepper jack for new flavors and textures.
Frequently Asked Questions
No, chilling is not required, but it is highly recommended. Refrigerating the assembled casserole for at least 1 hour (or overnight) allows the egg and milk mixture to fully soak into the bread, creating a custardy texture similar to French toast. This step helps the casserole bake up light, fluffy, and evenly cooked.
Cut the bread into cubes, spread them on a baking sheet, and place in a 300°F oven for 10 to 15 minutes until slightly dried out but not toasted. This creates the same effect as day-old bread, helping the cubes absorb the egg mixture without becoming soggy.
Yes. Assemble the casserole as directed using cubed bread, then transfer everything to a greased slow cooker insert. Cook on low for 7 to 8 hours or overnight until the eggs are fully set. Avoid using the high setting, as it can cause the edges to dry out before the center is fully cooked.
Yes. Grease a 12-cup muffin tin and divide the bread and egg mixture evenly among the cups. Bake at 350°F for about 20 to 25 minutes, or until the centers are set. This is a fun way to make portable, single-serve breakfast casseroles.
Absolutely. You can freeze the unbaked casserole (wrapped tightly in plastic wrap and foil) for up to 3 months. Thaw it overnight in the refrigerator before baking. You can also freeze baked leftovers. Once cooled, slice the casserole into squares, and individually wrap each piece. Freeze for quick, grab-and-go breakfasts. Reheat in the microwave or oven until hot.
More Easy Breakfast Recipes
I can’t wait for you to try this easy breakfast casserole recipe! With its hearty bread base, savory sausage, custard-like eggs, and perfectly melted cheese, every bite is comforting and delicious.
If you make this recipe, I’d love to hear what you think! Please leave a comment and a star rating below, your feedback helps other readers discover (and enjoy) this recipe too. Thank you so much! 💛
Easy Breakfast Casserole Recipe
Ingredients
- 1 tablespoon olive oil, or butter
- 1 yellow onion, diced
- 1 pound ground sausage, pork, chicken, or turkey; Italian, sweet, or hot
- 8 large eggs
- 3 cups whole milk, or half-and-half
- ½ teaspoon salt, plus more to taste
- 1 teaspoon black pepper
- 1 teaspoon garlic powder
- 1 cup parmesan cheese, grated
- 1 cup gouda cheese, shredded
- 10 cups day-old-bread, cut into large cubes (brioche, challah, or sourdough work best)
- fresh parsley, to garnish
Instructions
- Lightly coat a 9×13-inch baking dish with nonstick spray.
- Heat the olive oil in a large skillet over medium heat. Add the onion and cook for 2-3 minutes, or until it has started to soften.
- Add the sausage and cook until the onion is completely soft and the sausage is browned. Remove from heat and cool to room temperature.
- In a large bowl, whisk together eggs, milk, salt, pepper, and garlic powder.
- Once the sausage has cooled, stir in the shredded cheeses and the cooled sausage mixture.
- Spread the cubed bread evenly in the prepared baking dish. Pour the egg and sausage mixture on top, pressing gently to help the bread absorb the liquid.
- Cover with foil and refrigerate for at least 1 hour or overnight for the best texture.
- When ready to bake, preheat the oven to 350°F. Bake covered for 35 minutes, then uncover and continue baking for 25 minutes more, or until the center is set and the top is golden brown.
- Rest for 5 to 10 minutes, then garnish with parsley and serve warm. Enjoy!
Notes
- Bread: Day-old bread absorbs the custard mixture better than fresh bread. To make bread “day-old” quickly, cube it and bake on a sheet pan at 300°F for 10 to 15 minutes.
- Protein Swaps: Try diced ham, oven-baked bacon, or even leftover shredded chicken as a substitute for sausage.
- Veggies: Add sautéed mushrooms, roasted butternut squash, spinach, or bell peppers for more flavor and nutrition.
- Make-Ahead: Assemble the casserole the night before, refrigerate, and bake in the morning.
- Storage: Leftovers can be stored in an airtight container in the fridge for up to 5 days. Freeze baked portions for up to 3 months and reheat in the oven or microwave until hot.
- The total baking time will vary. You know your casserole is ready when the edges are golden brown and the center is no longer jiggly.
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
Can you leave this in refrigerator overnight and bake in the morning?
Yes.
Chilling in the refrigerator for at least 1 hour (or up to overnight) allows the milk and egg mixture to soak into the day-old bread, making it nice and soggy and perfect for baking. Itโs the same idea as French toast; the best recipes allow the milk and eggs to soak into the slices of bread before cooking.
In the morning, just take it out and let it sit at room temperature while you preheat your oven, then bake as directed.
It may require additional time ๐
Add about a teaspoon or 2 of mustard to this recipe , with the wet ingredients and it makes the flavors pop
I am making this tomorrow. 10 cups of bread is equal to how much bread? Using sourdough. Everything I read says 20 slices that seems like a lot. How much do you use?
Around 15, assuming 2/3 of a cup per slice ๐
Thank you, I was wondering that myself. Any trick to making it day old if I bought the bread tonight?
To give fresh bread the slightly stale texture that’s often ideal for casseroles, especially those like bread pudding or stuffing where you want the bread to absorb a lot of flavor without becoming too soggy, you can use a quick oven-drying technique. Hereโs how to do it:
Preheat your oven to about 300ยฐF (150ยฐC).
Slice or cube the bread depending on what your recipe calls for. This increases the surface area, allowing more moisture to escape, which helps the bread dry out more evenly and quickly.
Spread the bread pieces in a single layer on a baking sheet. If you’re using slices, you might want to split them into half or quarters.
Bake the bread in the preheated oven for about 10-20 minutes. Check periodically to make sure it’s drying without browning too much. If it starts to take on too much color, you can turn off the oven and let the bread sit inside as the oven cools down.
Remove from the oven and let the bread cool. It should feel dry to the touch and slightly harder than when it was fresh. If it’s not quite there yet, you can pop it back in the oven for a few more minutes.
This method effectively simulates the drying-out process that naturally occurs to bread over a day or so, making it perfect for recipes that require a sturdier, more absorbent bread.
Can you cook this in a crock pot?
Per the tip above in the main post:
”
Slow Cooker Breakfast Casserole:
This breakfast casserole is easy to make in the crock pot. Prepare it the night before, set your slow cooker to low, and let it cook while you sleep.
Spray the bowl of your slow cooker with non-stick olive oil or butter cooking spray.
Cook the onion and sausage in a large skillet over medium heat until cooked through. Transfer to the slow cooker with the day-old bread cubes.
Whisk together the eggs, milk, cheese, salt, black pepper, and garlic powder until fully combined, and pour over the sausage and bread. Mix to combine everything together.
Cook for 7-8 hours or until the eggs are fully cooked. Do not cook on high heat.
“
This sounds really good and easy with endless possibilities for variations. Have you ever tried mixing all the ingredients together and then baking them off in a muffin tin for individual servings? If so, are there any changes to the baking time etc. that I should make?
Yes, transforming a traditional breakfast casserole recipe into individual servings using a muffin tin is a fantastic idea for convenient, portion-controlled eating. When doing so, it’s important to adjust the baking time, as the smaller size of the muffin cups allows the mixture to cook more quickly than a single, large casserole dish. Typically, these mini casseroles may be ready in about 15-20 minutes, depending on the specific ingredients and oven temperature. Keep a close eye on them and test for doneness with a toothpick inserted into the center; it should come out clean when they’re fully cooked. This method not only offers a quick and easy serving option but also adds a delightful presentation to your breakfast table.
Do you use Italian sausage?
This recipe can be made with hot or sweet Italian sausage or your favorite breakfast sausage ๐
Never found the recipe
Its directly above in the Breakfast Casserole Recipe Card ๐
It turned out great, thanks!
Can you use shredded potatoes instead of bread?
I have not tried that, but the potatoes will have more moisture than the bread.
Maybe try my Tatertot breakfast casserole instead?