This easy Croissant Breakfast Casserole features croissants filled with sausage, onion, peppers, and cheese and baked with custardy eggs. If you’re looking for an easy breakfast or brunch recipe, this is it! I love this Croissant Breakfast Casserole for the holidays because it’s so easy to throw together.

You can prep this breakfast casserole in advance, it feeds a crowd, and it’s perfect for Christmas brunch. This Croissant Breakfast Casserole is all prepped the night before so all you have to do is pop it in the oven in the morning and relax!

What could be better than that?

The Best Croissant Breakfast Casserole

We love make ahead breakfast casseroles at our house just like this Croissant Breakfast Casserole!  They’re perfect for stress-free mornings whether for birthdays, holidays or just a special Sunday breakfast.

This croissant breakfast casserole is loaded with buttery croissants, sausage, onions, peppers, and cheese baked with custardy eggs. It’s a hearty and delicious breakfast that feeds a crowd–perfect for the holidays! Imagine a hearty sausage scramble but with toasty bits of croissant and that’s what you’ve got here.

We always have a Christmas brunch gathering and we make a whole spread. This Croissant Breakfast Casserole is definitely on the list this year along with Homemade NY Style Bagels, Salmon Gravlax, Smoked Salmon Spread, and Cranberry-Almond Danishes. Don’t forget the mimosas!

All the recipes above can be prepped in advance making Christmas brunch a relaxed affair on the chef! This croissant breakfast casserole is easy to customize for your guests and is such a crowd pleaser.

If you’re looking for a sweet breakfast casserole, try this Apple Pie French Toast Bake!

Why You’ll Love this Recipe

Easy – Who doesn’t want an easy breakfast during the holidays? There’s always so much going on that having an easy breakfast recipe in your back pocket is a must. This croissant breakfast casserole will make your holiday morning that much easier!

Make Ahead Friendly – This is the perfect recipe to make ahead of time and bake off just before your holiday meal. Prep the night before you plan to serve and pop it in the oven the morning of. Hosting doesn’t get much easier than that!

Crowd-Worthy –  This Croissant Breakfast Casserole serves a hearty 8-10 portions. This recipe is always a crowd favorite when we have company and is so hearty and filling.

How to Make Croissant Breakfast Casserole

I always use a ceramic or glass 9×13 baking dish for this recipe. I don’t recommend baking the casserole in aluminum.

Tools Needed

• 9×13 Baking Dish
• Baking Sheet
• Skillet
• Sharp Knife
• Mixing Bowl
• Whisk

Ingredients and Substitutions

• Croissants. Buy already baked small croissants from the bakery section of your grocery store, not from the tube.
• Sausage. Use your favorite breakfast sausage here! Buy the ground sausage, not the cased sausaged. If it’s in casings, you’ll have to remove the meat from the casings.
• Peppers & onions. A classic combo! Use whatever colors you like.
• Eggs. Use large eggs at room temperature.
• Half and half. Don’t downgrade to milk, the fat in the half and half makes the eggs custardy and delicious without being spongy.
• Cheese. I used white cheddar, but you can use anything you like!
• Cream cheese. Cream cheese helps bind the filling. Make sure to bring your cream cheese to room temperature.
• Spices & seasonings. Paprika, hot sauce, dijon mustard, and everything bagel seasoning make this Croissant Breakfast Casserole extra savory.
• Green onions. Top with some sliced green onions before serving.

The Process

1. Brown the meat and veggies. Heat a bit of oil in a skillet and brown the sausage, using a spoon to break it apart as it cooks. Once it’s mostly cooked, add the diced onion and bell pepper and cook until the veggies are soft. Set aside to cool to room temperature.
2. Mix the filling. In a bowl, combine the sausage mixture, cream cheese, cheese, paprika, and sliced green onions. Mix until smooth.
3. Prep the croissants. Cut the croissants in half length-wise. Lightly grease a 9×13 baking dish and arrange the bottom halves of the croissants in the baking dish.
4. Fill. Divide the sausage mixture between the croissant bottoms and then top with the top halves. Set aside.
5. Mix the eggs. In a blender, or in a mixing bowl, whisk the eggs, half and half, dijon, hot sauce, and salt and pepper until very smooth. If whisking by hand, make sure the eggs are very smooth and uniform.
6. Pour and set. Reserve 2 tablespoons of egg mixture and set aside. Pour the remaining egg mixture around the croissants. Cover and let them soak for at least 1 hour or overnight.
7. Bake. Before baking, brush the croissants with the reserved egg mixture and sprinkle with the everything bagel seasoning. Top with a bit more shredded cheese. Cover and bake at 375 F for 30 min. Uncover and bake the croissant breakfast casserole for 15-20 minutes longer, until the eggs are set and no longer runny. Top with more sliced green onions and serve warm.

Tips for Making this Croissant Breakfast Casserole

This Croissant Breakfast Casserole is so easy to make, but there are always tricks to make it better! Here are all my tips for making the perfect casserole every time.

• Prepare your baking dish:  Don’t forget to lightly grease your 9×13-inch baking dish with nonstick cooking spray otherwise your croissant breakfast casserole will stick!
• Use quality croissants:  This isn’t the time for pop and bake croissants.  You want medium to large croissants from the bakery section of the grocery store because they have more fabulous flaky layers for the custard to hide in.
• Submerge the croissants in the custard.  After you’ve added the last of the custard to the casserole, press the croissants down gently with your hands so that most of the croissants are submerged in the custard.  The tops will be exposed which is okay!
• Let the croissants soak. Letting the croissants soak allows them to absorb the eggy custard! Do this for about an hour before baking, or you can prep the croissant breakfast casserole the night before you plan to serve.
• Don’t over-bake. This casserole can end up dry if you over bake it. Bake just until the eggs are set and no longer runny.
• Don’t prep too far in advance. The earliest I would prep this casserole is the night before you plan to serve it (10-12 hours in advance).

Storing and Reheating Croissant Breakfast Casserole

This croissant breakfast casserole should be tightly covered or stored in an aright container in the refrigerator for up to 4 days. 

You can reheat leftover Croissant Breakfast Casserole two ways:

• Microwave:  The microwave is good for instant pleasure and individual pieces but you will lose some of the crispyness.  To microwave, add individual slices to a microwave safe plate and microwave for one minute.  Continue to microwave at 30 second intervals if needed to heat through.
• Oven.  Reheating leftover breakfast croissant casserole in the oven will yield the best results.  Cover casserole with foil and bake at 325 degrees F for 20 minutes or until warmed through.

To freeze after baking:

• Allow casserole to cool completely.
• Tightly wrap casserole in plastic wrap and then into a freezer-safe ziplock bag. Press out as much air as possible before sealing as this helps prevent freezer burn.
• Freeze for up to 2 months
• When ready to cook, thaw casserole in the refrigerator overnight.
• Reheat in the oven at 325 degrees F for 20 minutes or until warmed through

Ways to Customize Croissant Breakfast Casserole

There are so many ways to adjust this recipe! Think of this Croissant Breakfast Casserole as a blueprint that you can adjust to your tastes and what you have on hand. Here are my favorite ways to mix things up:

Try a different meat. Any ground meat here would work! I love breakfast sausage, but you can swap anything in. You could also use finely diced ham and bacon mixed together for almost a Denver scramble kind of casserole.

Swap a different cheese. White cheddar is classic, but there are so many options! Gruyere, sharp cheddar, Swiss, and even crumbled goat cheese or feta would be incredible here.

Add some veggies. If you want to add a bit more texture and sneak in some veggies, this is the chance to do so! You could add some sautéed spinach or kale, mushrooms, diced tomatoes, jalapeño, zucchini, etc. The sky is the limit here!

We love this Croissant Breakfast Casserole as part of our Christmas tradition and I hope you’ll give it a try too. It’s one of our favorite recipes, and I know you will love it just as much as we do! If you do give it a try, be sure to let me know! Leave a comment with a star rating below. You can also snap a photo & tag @JENNYGOYCOCHEA on Instagram. I LOVE hearing about & seeing your SMF creations!

More Easy Brunch Recipes to Try

Cranberry-Almond Danishes
Dutch Baby with Cranberry Compote
Bacon-Leek Frittata
Skillet Huevos Rancheros
Migas Breakfast Tacos

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