Festive Christmas Breakfast Casserole: The Ultimate Holiday Brunch Dish

Custard-soaked croissants bake to golden perfection, with gooey cheese and zesty peppers.

By Medha deb

Created on Sep 17, 2025

Custard-soaked croissants bake to golden perfection, with gooey cheese and zesty peppers.

Christmas Breakfast Casserole: A Holiday Favorite

There’s nothing quite like waking up to the aroma of a decadent, bubbling breakfast casserole on Christmas morning. This festive dish, overflowing with gooey cheese, flaky croissants, hearty ham, and colorful bell peppers, is designed to unite family and friends around the table before the gift-unwrapping begins. Easy to prepare in advance and just as delightful reheated, this casserole will quickly become a cherished part of your holiday tradition.

What Sets This Christmas Casserole Apart?

Unlike traditional breakfast bakes that lean heavily on bread or hash browns, this holiday version uses buttery croissants as the base, lending a rich, tender texture to every bite. The combination of deli ham, two kinds of cheese, and a custard of eggs, milk, and half-and-half ensures a creamy, crave-worthy dish. The addition of fresh thyme and a touch of hot sauce brings balance and depth, complementing the sweet–savory contrast from the red and green peppers—nature’s own Christmas colors.

Ingredients You’ll Need

Olive Oil: Adds moisture, helps sauté vegetables, and flavors the casserole.
Deli Ham: Use 8 ounces of diced ham or substitute turkey or crumbled cooked sausage for a different flavor profile.
Onion: A medium one, diced finely for subtle sweetness and depth.
Red Bell Pepper: Diced, for sweetness and festive color.
Green Bell Pepper: Diced, for earthiness and visual appeal.
Kosher Salt and Black Pepper: For seasoning and balance.
Fresh Thyme: Chopped, to brighten and freshen the dish.
Croissants: Six large, cut into 1.5- to 2-inch pieces. Use day-old croissants for the best soak and texture.
Milk and Half-and-Half: The blend creates a rich but light custard.
Hot Sauce: Just a teaspoon to subtly enhance flavor without adding heat.
Eggs: Five large eggs hold the casserole together.
Cheese: Two cups white cheddar and one cup pepper jack, both grated and divided. The mix offers sharpness and a gentle kick.

Step-by-Step: How to Make Christmas Breakfast Casserole

Prepare the Vegetable and Ham Mixture:
Heat a tablespoon of olive oil in a large skillet over medium-high. Add diced ham, onion, and both bell peppers. Sauté, stirring frequently, until the veggies are soft and translucent—about 8 to 10 minutes. Stir in salt, pepper, and thyme, cook for another minute, then remove from heat and let cool slightly.
Assemble the Casserole Base:
Brush a 13-by-9-inch baking dish with the remaining olive oil. Scatter the croissant pieces in the dish. Spoon the ham and veggie mixture over the croissants, gently mixing to combine and distribute evenly.
Related: Ultimate Crescent Roll Breakfast Casserole Recipe
Whisk the Custard:
In a medium bowl, thoroughly whisk together the milk, half-and-half, hot sauce, and eggs. Stir in half the cheddar and half the pepper jack cheese.
Combine Everything:
Pour the egg and cheese mixture over the croissants and ham mixture in the baking dish. Gently toss to ensure all croissant pieces are moistened and the fillings are distributed throughout. Cover and refrigerate for at least one hour and up to four hours so the croissants soak up the custard, ensuring a creamy texture post-bake.
Bake the Casserole:
Preheat your oven to 350°F (177°C). Take the dish from the refrigerator, uncover it, and let it sit at room temperature for 15 minutes. Using a spatula, press down gently on the croissants to help them absorb the custard. Sprinkle the remaining cheddar and pepper jack cheese on top. Bake for approximately 45 minutes, or until puffed, golden, and the cheese is melted and bubbly. Let rest for 15 minutes before serving.

Preparation Tips for a Flawless Casserole

Use Day-Old Croissants: Stale croissants absorb the custard best and prevent a soggy texture.
Pre-Cut Ingredients: Dice ham and vegetables the night before to streamline morning assembly.
Customize the Filling: Swap in cooked sausage, leftover turkey, or even sautéed mushrooms and spinach to change up flavors.
Cheese Variations: Try sharp cheddar, gruyere, or smoked gouda for new taste dimensions. Pepper jack adds a subtle kick, but this can be omitted or doubled based on preference.
Don’t Skip the Resting Time: Allowing 15 minutes for the casserole to rest after baking ensures clean slices and an even, creamy texture.

Make-Ahead & Storage Guide

This casserole was designed for ease during busy holidays. Assemble it the night before and simply bake the next morning. It stores well chilled and can be reheated, maintaining its creamy interior and crisp, cheesy crust.

Overnight Prep: Assemble as instructed, cover with foil or plastic wrap, and refrigerate up to 12 hours.
Freezer-Friendly: Once baked and cooled, wrap individual portions tightly and freeze for up to 2 months. Reheat in the oven or microwave before serving.
Storing Leftovers: Refrigerate in an airtight container for up to 3 days. Briefly reheat in the oven (covered) to maintain crispness.

Serving Suggestions

This hearty Christmas breakfast casserole is a meal in itself, but you can complete your holiday brunch with a few festive sides and beverages:

Fresh fruit salad to brighten the table.
Crispy bacon or sausage links for extra heartiness.
Sweet pastry, muffins, or cinnamon rolls for those with a sweet tooth.
Holiday drinks such as orange juice, coffee, or even a breakfast punch.

Common Variations

Variation	How to Make It
Vegetarian	Omit ham and add sautéed mushrooms, spinach, or extra peppers.
Spicy	Double the hot sauce or use spicy pepper jack and add diced jalapenos.
Kid-Friendly	Use mild cheddar cheese, omit hot sauce, and substitute with turkey or chicken if ham is not preferred.
Gluten-Free	Replace croissants with a gluten-free bread or pre-cooked gluten-free hash browns.

Troubleshooting & Expert Advice

Why is my casserole soggy? Ensure croissants are slightly stale and don’t over-soak. Avoid underbaking—the casserole should be set in the center.
Can I add more vegetables? Absolutely! Just sauté extra veggies until any moisture cooks off to prevent a watery result.
How to make ahead for a large group? Double the recipe and use two 13×9 pans. These bake well side-by-side.
Quick tip: Letting the casserole sit before slicing makes serving easier and prevents the filling from falling apart.

Frequently Asked Questions (FAQs)

Q: Can I substitute croissants with another bread?

A: Yes, you can use brioche, challah, or sturdy sandwich bread. However, croissants add a unique buttery flavor and tender texture.

Q: How far ahead can I assemble this casserole?

A: The casserole can be assembled up to 12 hours before baking. Store it covered in the refrigerator overnight for easy morning preparation.

Q: Can I make this casserole without ham?

A: Certainly. Replace the ham with cooked sausage, turkey, or sautéed mushrooms for a vegetarian option.

Q: What cheeses work best in this recipe?

A: The suggested mix of white cheddar and pepper jack offers sharpness and creaminess, but you can experiment with gruyere, Swiss, or smoked cheeses for different flavors.

Q: How do I store and reheat leftovers?

A: Store leftovers in an airtight container in the fridge for up to 3 days. Reheat single servings in the microwave or larger portions covered in the oven at 325°F until warmed through.

Final Thoughts: A New Holiday Tradition

This Christmas breakfast casserole brings together golden croissants, savory ham, vibrant peppers, and a duo of cheeses, harmonized into a creamy, crowd-pleasing bake. With make-ahead flexibility, easy customization, and festive appearance, it’s sure to become the centerpiece of your family’s Christmas morning for years to come.

References

Author

medha deb

Medha Deb is an editor with a master's degree in Applied Linguistics from the University of Hyderabad. She believes that her qualification has helped her develop a deep understanding of language and its application in various contexts.

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