This croque monsieur casserole turns the classic French sandwich into an easy, oven-baked comfort dish with layers of buttery bread, melty cheese, and savory ham. Perfect for brunch or make-ahead dinners, it delivers rich, cozy flavor in every bite.
What Is a Croque Monsieur Casserole?
A Croque Monsieur Casserole is a baked version of the traditional French ham and cheese sandwich.
Instead of assembling individual sandwiches, everything is layered into a baking dish and baked until golden, bubbly, and irresistible.
This dish works beautifully as:
- A French breakfast casserole
- A savory brunch bake
- A weekend comfort food recipe
Ingredients
Casserole Base
- 8 slices white bread or brioche, cubed
- 2 cups cooked ham, diced or sliced
- 2 cups Gruyère cheese, shredded
Creamy Custard Sauce
- 4 large eggs
- 1½ cups whole milk
- ½ cup heavy cream
- 2 tablespoons Dijon mustard
- ½ teaspoon salt
- ½ teaspoon black pepper
- ¼ teaspoon nutmeg (classic French flavor)
Optional Topping
- ½ cup shredded Gruyère or Swiss cheese
- 2 tablespoons melted butter
Step 1: Preheat the Oven
Preheat your oven to 375°F (190°C).
Lightly grease a 9×13-inch baking dish with butter or non-stick spray.
Step 2: Layer the Bread and Ham
Spread the cubed bread evenly across the bottom of the dish.
Scatter the ham over the bread, followed by half of the shredded Gruyère cheese.
Step 3: Make the Custard Sauce
In a large bowl, whisk together eggs, milk, cream, Dijon mustard, salt, pepper, and nutmeg until fully combined.
This creamy mixture mimics the béchamel sauce used in a traditional Croque Monsieur.
Step 4: Assemble the Casserole
Slowly pour the egg mixture over the bread and ham layers. Press gently so everything absorbs the custard.
Sprinkle the remaining cheese on top.
Step 5: Bake Until Golden
Bake uncovered for 35–40 minutes, or until the casserole is set in the center and the top is golden brown and bubbling.
Let rest for 5–10 minutes before serving.
Make-Ahead Croque Monsieur Casserole
This recipe is perfect for overnight breakfast casseroles.
Assemble the night before
Cover tightly and refrigerate up to 24 hours
Bake fresh in the morning
If baking straight from the fridge, add 5–10 minutes to bake time.
Serving Suggestions
Serve your Croque Monsieur Casserole with:
- A light green salad
- Fresh fruit or berries
- Simple roasted potatoes
- Coffee or mimosas for brunch
Storage & Reheating Tips
- Refrigerator: Store leftovers in an airtight container for up to 4 days
- Freezer: Freeze portions for up to 2 months
- Reheat: Warm in the oven at 325°F or microwave individual slices
Croque Monsieur Casserole Variations
- Croque Madame Casserole: Add a fried or baked egg on top
- Turkey & Swiss: Swap ham for turkey
- Gluten-Free: Use gluten-free bread
- Extra Crispy: Sprinkle breadcrumbs on top before baking
Frequently Asked Questions
What’s the difference between Croque Monsieur and Croque Madame?
A Croque Madame includes a fried egg on top—easy to add after baking this casserole!
Can I use Swiss cheese instead of Gruyère?
Yes! Swiss, Emmental, or even a Gruyère blend work well.
Final Thoughts
This Croque Monsieur Casserole is everything you love about French café food—comforting, cheesy, and elegant, yet incredibly easy to make.
Whether you’re hosting brunch or meal-prepping for the week, this recipe delivers every time.
