Dinner

Irresistible Overnight Croissant Breakfast Casserole Recipe

Byluca Carter January 31, 2026January 31, 2026

Introduction

This Overnight Croissant Breakfast Casserole is a delightful make-ahead dish perfect for holidays, brunch, or busy mornings. Featuring buttery croissants, savory sausage, creamy eggs, and melted cheese, it offers a warm and flaky breakfast that you’ll crave again and again.

The image shows a white baking dish filled with a golden brown savory pie that has a thick, puffy crust around the edges, which is slightly crispy and dark golden. Inside, there is a creamy yellow layer with melted cheese on top that has bubbly browned spots. Underneath the cheese, chunks of mushrooms and a creamy mixture of potatoes or eggs can be seen, revealing a smooth texture mixed with tender pieces. There are a few fresh green parsley leaves placed in the center on top as garnish, adding a pop of green color. The dish sits on a white marbled surface, with a blurred background of a white bowl with green herbs and a red bottle. photo taken with an iphone --ar 4:5 --v 7

Ingredients

5 large croissants (preferably day-old), torn into large chunks
1 lb (450g) ground sausage, cooked and drained

1 cup (120g) shredded cheddar cheese
6 large eggs

2 cups (475ml) whole milk
1 teaspoon salt

½ teaspoon black pepper
½ teaspoon garlic powder
½ teaspoon onion powder

Fresh parsley, chopped (optional, for garnish)

Instructions

Step 1: Grease a 9×13-inch baking dish with cooking spray or butter. Layer torn croissants evenly in the dish. Sprinkle cooked sausage and shredded cheddar cheese over the croissants.
Step 2: In a large bowl, whisk together the eggs, milk, salt, pepper, garlic powder, and onion powder. Pour the mixture evenly over the croissant layers. Gently press down with a spatula to help the croissants soak up the custard.

Step 3: Cover the dish with foil and refrigerate for at least 6 hours or overnight to allow the flavors to meld and the croissants to absorb the custard.
Step 4: Preheat your oven to 350°F (175°C). Uncover the casserole and bake for 40–45 minutes, or until golden brown and set in the center. Let cool for 10 minutes before garnishing with fresh parsley and serving warm.

Tips & Variations

Use day-old croissants for the best texture; fresh croissants may become soggy.

Try swapping the sausage for cooked turkey, chicken, or plant-based alternatives.
Experiment with different cheeses like Swiss, Monterey Jack, or mozzarella for varied flavors.
Add sautéed spinach, mushrooms, or bell peppers for extra veggies.

For a spicy touch, add a dash of hot sauce or red pepper flakes to the egg mixture.
Broil the casserole for 1–2 minutes at the end of baking if you prefer a crispier top.

Storage

Store any leftovers covered in the refrigerator for up to 3 days. To reheat, warm individual portions in the microwave until heated through. This casserole is also freezer-friendly both before and after baking; thaw overnight in the refrigerator and reheat thoroughly before serving.

How to Serve

The dish is a baked pie in a white ceramic round dish with handles, placed on a white marbled surface. The pie has a thick outer crust that is golden brown and flaky, forming a raised border with folds. Inside, there are two main visible layers: a top layer of melted cheese with a bubbly, golden appearance, and a lower layer of creamy filling mixed with chunks of brown mushrooms and small bits of yellow corn. Fresh green parsley leaves are scattered on top, adding a touch of color. A small portion of the pie is missing, showing the creamy texture inside. Photo taken with an iphone --ar 4:5 --v 7

Serve this delicious recipe with your favorite sides.

FAQs

Can I use fresh croissants instead of day-old?

While you can use fresh croissants, day-old croissants work best as they absorb the custard without becoming too soggy, resulting in better texture after baking.

Can I prepare this casserole without sausage?

Yes, you can omit the sausage or substitute it with cooked turkey, chicken, plant-based sausage, or additional vegetables to suit your taste or dietary needs.