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Flaky, Savory & Perfect for Make-Ahead Mornings
This Overnight Ham & Cheese Croissant Casserole is everything you want in a breakfast bake: rich, flaky, cheesy, and ridiculously easy to prep the night before. Made with buttery croissants, savory diced ham, and melty Swiss cheese, all soaked in a creamy egg custard—this casserole delivers classic comfort with minimal effort. Whether you’re hosting brunch or just feeding a hungry family, this is your new go-to.
Ingredients
For the Casserole:
- 5–6 large croissants (day-old preferred), roughly torn into pieces
- 1 1/2 cups diced cooked ham
- 1 1/2 cups shredded Swiss cheese (or Gruyère for extra richness)
- 6 large eggs
- 1 3/4 cups whole milk
- 1/2 cup heavy cream
- 1 tablespoon Dijon mustard (optional but delicious)
- 1/2 teaspoon garlic powder
- 1/4 teaspoon black pepper
- Pinch of salt (adjust based on saltiness of ham)
Optional Toppings:
- Extra shredded cheese for the top
- Fresh chives or parsley for garnish
Instructions
1. Prep the Dish
Lightly grease a 9×13-inch baking dish. Layer the torn croissants evenly in the dish, followed by the diced ham and shredded cheese.
2. Make the Custard
In a large bowl, whisk together the eggs, milk, cream, Dijon mustard, garlic powder, pepper, and salt until well combined.
3. Assemble
Pour the custard mixture evenly over the croissant and ham layers. Gently press down on the croissants so they soak up the custard.
4. Chill Overnight
Cover the dish tightly with foil or plastic wrap and refrigerate overnight (or at least 6 hours). This allows the croissants to fully absorb the custard and develop flavor.
5. Bake
Preheat oven to 350°F (175°C). Remove casserole from the fridge and let sit at room temperature for 20–30 minutes. Bake uncovered for 40–45 minutes, or until golden on top and set in the center. If the top browns too quickly, tent loosely with foil.
6. Serve
Let cool slightly before slicing. Garnish with fresh herbs if desired, and serve warm.
Tips & Variations
- Make it cheesy: Add a mix of cheeses like cheddar or mozzarella for a richer flavor.
- Add veggies: Sautéed spinach, mushrooms, or bell peppers work great.
- No Swiss? Use cheddar, Monterey Jack, or a mix of whatever’s in your fridge.
Nutrition Overview (Estimated per serving, serves 8–10)
- Calories: 360
- Protein: 20g
- Carbs: 18g
- Fat: 24g
- Fiber: 1g
- Sugar: 3g
Storage & Reheating
- Refrigerator: Store leftovers covered for up to 4 days.
- Freezer: Wrap individual slices and freeze for up to 2 months.
- Reheat: Warm in a 325°F oven or microwave until heated through.
How to Scale It Up
- Doubling the recipe? Use two 9×13-inch pans or a larger deep-dish roasting pan. Add 5–10 minutes to the bake time and check for doneness in the center.
Final Thoughts
This Overnight Ham & Cheese Croissant Casserole is the definition of easy elegance. It feels indulgent but is simple to prepare ahead of time—making it perfect for holidays, weekend guests, or meal prepping breakfast for the week. With minimal prep and maximum flavor, it’s the kind of dish you’ll want on repeat all season long.
Looking for more easy make-ahead breakfast ideas to feed your family or wow your brunch guests? This breakfast casserole recipe is just one of 12 crowd-pleasing make-ahead breakfast casseroles featured in our full roundup.
From cheesy sausage bakes to sweet French toast casseroles, each recipe is designed to be prepped ahead and baked fresh in the morning—perfect for holidays, weekends, or meal prep.
Browse all 12 make-ahead breakfast casseroles here:
https://divahomeinspiration.com/12-make-ahead-breakfast-casseroles-to-feed-a-crowd/
