Overnight Croissant Breakfast Casserole

Introduction

Start your morning on a high note with this Overnight Croissant Breakfast Casserole, a brilliant blend of buttery croissants, creamy eggs, melty cheese, and savory add-ins. This effortless recipe combines crowd-pleasing flavors with make-ahead convenience—just assemble the night before and bake for a stress-free breakfast or brunch that impresses every time.

Whether you’re hosting a holiday gathering, prepping a special weekend treat, or simply craving a cozy breakfast that requires minimal morning effort, this casserole delivers satisfying comfort and gourmet flair.

Why Make an Overnight Croissant Breakfast Casserole?

What sets this recipe apart is its perfectly balanced texture: flaky croissants soak up a rich egg custard overnight, resulting in a casserole that’s wonderfully crisp on top with a luxuriously tender center. Customizable additions—like vegetables, breakfast meats, or herbs—mean you can tailor it to your taste or use whatever you have in the fridge, making it both practical and indulgent.

Choosing Ingredients for Maximum Flavor

Start with day-old croissants, which are ideal for soaking up the savory custard without becoming soggy. Fresh eggs and whole milk form the creamy base, while shredded cheese and your choice of mix-ins (like ham, spinach, or roasted peppers) add depth and personality. Enhance the dish with a sprinkle of fresh herbs before baking for a café-style finish.

For chopping onions, peppers, or other veggies, the Mueller Pro-Series 10-in-1, 8 Blade Vegetable Chopper can save you time and ensure uniform pieces for even cooking.

Simple Assembly, No Morning Rush

After assembly, the casserole chills overnight, soaking up all the delicious flavors. In the morning, all you need to do is pop it in the oven—no more scrambling to make breakfast from scratch! For easy cleanup and flawless release, line your baking dish with a sheet of Reynolds Kitchens Brown Parchment Paper Roll.

If shredding cooked chicken or ham for your casserole, reach for a Chicken Shredder Tool Twist—it quickly breaks down your protein for perfect, bite-sized morsels.

Serving Suggestions to Make Your Morning Special

Present your casserole in a beautiful dish and pair with a bright fruit salad for contrast. This make-ahead bake also travels well—pack leftovers in a Bentgo Salad Container for a portable brunch or breakfast-on-the-go.

For a coordinated brunch table, protect your surface with a practical, easy-to-clean Pureegg Plastic Table Cloth Disposable 10 Pack—perfect for mess-free entertaining.

Nutritional Information and Servings

This casserole easily serves 8–10 people. Depending on selected mix-ins and cheese, each serving contains roughly 320–420 calories, making it a hearty yet balanced start to your day.

Recipe Recap: The Ultimate Overnight Croissant Breakfast Casserole

With buttery croissants, creamy custard, and customizable fillings all baked into a golden, irresistible casserole, this dish proves that effortless can also be exceptional. Enjoy a crowd-pleasing breakfast that’s as easy to prepare as it is to love!

Instructions

1. Lightly grease a 9×13-inch baking dish, lining the bottom with a strip of Reynolds Kitchens Brown Parchment Paper Roll for easy cleanup.
2. Layer half of the croissant pieces on the bottom of the dish. Top with half the shredded cheese, ham (or protein), onion, and spinach or mushrooms. Repeat with remaining croissants, cheese, and fillings.
3. In a large bowl (or using the Ninja BL610 Professional 72 Oz Countertop Blender for extra smoothness), whisk eggs, milk, mustard, a pinch of salt, and several grinds of pepper.
4. Pour the egg mixture evenly over the casserole. Gently press down with the back of a spoon to help the custard soak into the croissants. Cover tightly with foil, and refrigerate overnight (or at least 4 hours).
5. When ready to bake, preheat the oven to 350°F. Uncover the casserole and bake for 40-45 minutes, or until the custard is set and the top is golden brown. Tent with foil if browning too quickly.
6. Allow to cool for 10 minutes, then garnish with chives or parsley. Cut into squares and serve warm.

Cook and Prep Times

Prep Time: 20 minutes (plus overnight chill)

Cook Time: 45 minutes

Total Time: 1 hour 5 minutes plus chilling