Okay, let’s talk about brunch. The real kind of brunch. Not the $19 avocado toast kind with a 45-minute waitlist—I’m talking about cozy family-style brunch at home, where you’re in slippers, the coffee pot is full, and everyone is still in their pajamas. That’s where this Easy Cheesy Croissant Breakfast Casserole shines.
This recipe is basically my secret weapon for holiday mornings, Sunday family brunch, or anytime I want to impress without actually doing that much. The flaky, buttery croissants soak up this ultra-creamy, cheesy egg custard, and the crispy bacon brings all the salty, savory goodness you could ask for. Two kinds of cheddar take it over the top.
The first time I made this was for Easter, and I’m not even kidding—it was gone before I could grab seconds. Now I make two: one for the table, one for leftovers (which reheat like a dream, by the way). It’s the kind of dish that feels fancy but is secretly so easy, and you can totally prep it the night before. AKA: brunch magic.
Ingredients:
Croissants:
Buttery, flaky croissants are the real MVP here. Their delicate layers soak up the egg mixture like a sponge, giving the casserole that perfect fluffy texture inside with crisp edges on top. I recommend using day-old croissants—they’re slightly dried out, which helps them absorb even more flavor. Plus, it’s a great way to use up leftovers from the bakery!
Bacon:
Salty, smoky, and perfectly crispy—bacon brings all the savory flavor this casserole needs. I like to cook it until it’s just shy of too crispy so it holds up after baking. Thick-cut is ideal for a satisfying bite, and honestly, it’s hard not to snack on a few pieces while assembling. You’ve been warned.
Eggs:
Eggs are the base that holds everything together in a breakfast casserole. When mixed with milk and cream, they bake into a soft, fluffy, custard-like layer. It’s what gives this dish that tender, melt-in-your-mouth feel. Use large eggs for the best balance.
Whole Milk + Heavy Cream:
This combo makes the egg mixture incredibly rich and velvety. Whole milk keeps things light enough, while the cream adds that luscious, indulgent texture. If you’re feeling extra fancy, you can even sub half-and-half. But I’m team cream all the way—it makes a difference.
Dijon Mustard:
This might sound unexpected, but trust me—it’s a little secret flavor booster. Just a tablespoon adds a subtle tang and brings out the sharpness of the cheddar. You won’t actually taste “mustard,” but you’ll notice a little extra something in the background. It’s like a flavor enhancer in disguise.
Cheddar Cheeses:
Sharp cheddar adds bold, tangy flavor, while white cheddar gives a creamy, melty finish. I like using both for that perfect cheesy balance. Always grate your own cheese if you can—it melts smoother and gives you that dreamy cheese pull. Pre-shredded is convenient, but freshly grated = next-level.
Salt + Pepper:
Simple but essential! A little salt brings all the flavors to life, especially in the egg custard. Don’t forget the pepper either—it adds a gentle warmth and rounds everything out. Taste your egg mixture before pouring to make sure it’s seasoned just right.
🥄 Equipment Needed for my Croissant Breakfast Casserole:
9×13-inch Baking Dish – This size is perfect for evenly baking the casserole and getting those golden, crispy edges.
Large Mixing Bowl – You’ll need plenty of space to whisk together the egg mixture and fold in all the goodies.
Whisk – Helps you fully combine the eggs, milk, and cream for a smooth, lump-free custard.
Sharp Knife & Cutting Board– For chopping bacon and slicing up those buttery croissants into bite-sized pieces.
Skillet or Sauté Pan – You’ll need this to cook the bacon until it’s perfectly crisp (aka irresistible).
Box Grater (if shredding cheese) – Freshly grated cheese melts like a dream—way better than pre-shredded!
Measuring Cups & Spoons – To make sure every ingredient is just right for the ultimate flavor and texture.
Variations + Substitutions:
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No bacon? Use breakfast sausage, ham, turkey bacon, or keep it veggie.
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Veggie-loaded version: Add sautéed mushrooms, bell peppers, onions, or spinach.
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Cheese swap: Try gruyère, mozzarella, Monterey Jack, or a mix of all three.
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Bread swap: If croissants aren’t your thing (gasp!), try brioche, sourdough, or even leftover dinner rolls.
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Dairy-free: Use dairy-free milk and cheese. Oat milk and vegan cheddar work surprisingly well!
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Gluten-free: Use GF croissants or bread to make this gluten-free.
Easy Cheesy Croissant Breakfast Casserole
Video
Ingredients
- 10 mini croissants , preferably 1–2 days old or 5 regular
- 1 lb thick-cut bacon
- 8 large eggs
- 2 cups whole milk
- ½ cup heavy cream
- 1 tbsp Dijon mustard
- Salt and black pepper to taste
- 4 oz white cheddar cheese, grated about 1 cup
- 4 oz sharp cheddar cheese, grated about 1 cup
- Butter or nonstick spray for greasing
Instructions
1. Prep the Croissants
- Roughly chop croissants into 1-inch pieces. If you’re using minis, I do about 6 pieces per croissant. If you’re using full-sized ones, go for 10–12 pieces each. You want them bite-sized, but not too small—they’ll shrink a little when baked.
2. Cook the Bacon
- Cut bacon into bite-sized pieces and cook in a large skillet over medium heat until crispy (about 8–10 minutes). Use a slotted spoon to transfer bacon to a paper towel-lined plate to drain excess grease.
- Tip: Don’t toss the bacon grease! Save a little (like a tablespoon) and add it to the egg mixture for an extra savory boost.
3. Make the Egg Custard
- In a big mixing bowl, whisk together eggs, milk, cream, Dijon mustard, salt, and black pepper. Whisk it really well—you want everything fully combined and smooth.
- Stir in the cooked bacon and about ⅔ of the shredded cheese. The rest will go on top!
4. Assemble the Casserole
- Grease a 9×13 baking dish with butter or nonstick spray. Scatter the croissant pieces evenly in the pan. Pour the egg mixture over the top, pressing the croissants down gently with a spatula to help them soak it all up.
- Sprinkle the remaining cheese over the top—don’t be shy
5. Bake
- Bake at 350°F (175°C) uncovered for 40–45 minutes. The top should be golden and slightly puffed, and the center should be set (no jiggly middle). If it starts browning too fast, loosely tent with foil.
- Tip: Stick a knife in the center—if it comes out clean (no liquid egg), it’s done.
6. Rest and Serve
- Let it cool for 5–10 minutes before slicing. This gives the custard time to settle and makes it easier to cut.
Make-Ahead Instructions
- Option 1: Assemble Now, Bake LaterOnce it’s assembled, cover the dish tightly with foil and refrigerate overnight. The next morning, uncover and bake as directed. You might need an extra 5–10 minutes if it’s super cold from the fridge.
- Option 2: Bake Now, Reheat LaterBake the full casserole, let it cool, then refrigerate. Reheat individual portions in the microwave, or pop the whole thing in a 300°F oven for 15–20 minutes to warm it through.
Ingredient Notes + Tips:
Croissants: The more buttery, the better! Day-old croissants work best because they’re a little drier, which helps them absorb the egg mixture. I usually buy them the day before, let them sit on the counter overnight (loosely covered), and they’re perfect.
Bacon: Thick-cut is the move here. It crisps up beautifully and holds its texture after baking. I like to cut it before cooking—it cooks faster and more evenly that way.
Eggs + Dairy: The combo of whole milk and heavy cream creates that luscious, soft egg texture. If you’re out of cream, you can sub in more whole milk, but I highly recommend the cream if you want that indulgent brunch vibe.
Cheese: Grating your own cheese is KEY. Pre-shredded cheese has anti-caking agents that make it harder to melt smoothly. Use a block of cheddar—it’s worth the extra minute of grating.
Dijon mustard: This might seem random, but trust me—it brings out the flavor of the cheddar and gives the casserole a little oomph. You won’t taste mustard; it just makes the cheese pop.
Storage Instructions
Fridge: Store leftovers in an airtight container in the fridge for up to 4 days. It reheats beautifully!
Freezer: Freeze individual slices (wrap in plastic, then foil) for up to 2 months. Thaw overnight in the fridge and reheat in the microwave or oven.
Reheat:
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Microwave: 1–2 minutes
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Oven: 300°F for 10–15 minutes (best if you want crispy edges again)
More of my recipes
Do you LOVE Brunch? Try a Few More of my Brunch Favs:Brown Butter Carrot Coffee Cake with Pecan Streusel
Cinnamon Sugar French Toast Sticks Recipe
Fluffy Souffle Egg Sandwich Recipe
Conclusion
This casserole is what I like to call a low-effort, high-reward recipe. It’s buttery, savory, rich, and just feels a little fancy thanks to the croissants. Whether you’re feeding in-laws, hosting brunch with friends, or just want something warm and comforting for the week—this checks all the boxes.
And honestly, I think every good breakfast deserves bacon, cheese, and bread. This has all three, plus eggs. So it’s kind of perfect.
Let’s Be Brunch Besties!
If you make this Easy Cheesy Croissant Breakfast Casserole, I want to see it! Tag me on Instagram @munchiesbymallory so I can drool over your creations (and probably repost them). And don’t forget to leave a comment and review—it seriously helps my little blog grow!
Frequently Asked Questions
Can I make this croissant breakfast casserole ahead of time?
Yes, this casserole is perfect for making ahead. You can fully assemble it, cover it tightly, and refrigerate overnight. Bake it fresh in the morning, adding an extra 5 to 10 minutes if needed.
What kind of croissants work best for this recipe?
Day old croissants are ideal because they absorb the egg mixture better without becoming soggy. Mini croissants or regular sized bakery croissants both work well.
Can I substitute another type of bread for croissants?
Yes. Brioche, challah, sourdough, or leftover dinner rolls are great substitutes. Just aim for a bread that is slightly stale so it can soak up the custard properly.
Can I make this breakfast casserole without bacon?
Absolutely. You can swap the bacon for breakfast sausage, ham, turkey bacon, or keep it vegetarian by adding sautéed vegetables like mushrooms, spinach, or bell peppers.
What cheeses can I use instead of cheddar?
Gruyère, Monterey Jack, mozzarella, Colby Jack, or a mix of cheeses all work well. Freshly grated cheese is recommended for the best melting and texture.
Do I really need to use heavy cream?
Heavy cream gives the casserole its rich, custardy texture, but you can substitute half and half or use all whole milk if needed. The texture will be slightly lighter but still delicious.
How do I know when the casserole is fully cooked?
The top should be golden and slightly puffed, and the center should be set with no visible liquid. Inserting a knife into the center should come out clean.
Can I freeze croissant breakfast casserole?
Yes. You can freeze baked slices wrapped tightly in plastic wrap and foil for up to two months. Thaw overnight in the fridge before reheating.
How should I reheat leftovers?
Leftovers can be reheated in the microwave for 1 to 2 minutes or in a 300°F oven for 10 to 15 minutes if you want to bring back crispy edges.
Is this recipe good for feeding a crowd?
Yes, this recipe serves about 12 people and is ideal for holidays, brunch parties, and family gatherings. It is easy to double if needed.
Can I make this recipe gluten free or dairy free?
You can make it gluten free by using gluten free croissants or bread. For dairy free, use dairy free milk and cheese alternatives. The texture may vary slightly but it still works well.
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