Croque-Monsieur Gratiné is a classic French comfort food featuring crisp golden bread layered with savory ham, melted cheese, and a luxurious homemade béchamel sauce. Baked until bubbling and beautifully browned, it’s perfect for breakfast, brunch, lunch, or a cozy dinner.
Ingredients
For the Sandwiches
- 8 slices white sandwich bread or brioche
- 8 slices cooked ham
- 1½ cups grated Gruyère cheese
- ½ cup grated Parmesan cheese
- 2 tbsp butter, softened
- ½ tsp Dijon mustard, optional
- Freshly ground black pepper, to taste
For the Béchamel Sauce
- 3 tbsp unsalted butter
- 3 tbsp all-purpose flour
- 1½ cups whole milk, warmed
- ¼ tsp salt
- ¼ tsp black pepper
- ¼ tsp ground nutmeg
- ½ cup grated Gruyère cheese
Instructions
1. Make the Béchamel
Melt the butter in a saucepan over medium heat.
Add the flour and whisk continuously for about 1–2 minutes to create a smooth roux. Don’t let it brown.
Gradually pour in the warm milk while whisking constantly to prevent lumps.
Continue cooking for 4–6 minutes, stirring frequently, until the sauce thickens enough to coat the back of a spoon.
Season with salt, black pepper, and nutmeg.
Remove from the heat and stir in ½ cup Gruyère until melted and smooth.
2. Prepare the Bread
Preheat your oven to 425°F (220°C).
Spread a thin layer of softened butter over one side of each bread slice.
Place the slices butter-side down on a baking sheet.
Toast for approximately 5 minutes, or until lightly golden.
Remove from the oven.
3. Assemble the Sandwiches
Spread a small amount of Dijon mustard on four slices of toasted bread if desired.
Top each with two slices of ham and a generous amount of grated Gruyère.
Season lightly with black pepper.
Place the remaining bread slices on top.
4. Add the Béchamel
Spread a generous layer of the Gruyère béchamel over the top of each sandwich.
Sprinkle the remaining Gruyère and Parmesan evenly over the béchamel.
The cheese should cover the tops generously so it becomes beautifully golden and bubbly in the oven.
5. Bake Until Golden
Place the sandwiches in the oven and bake for approximately 8–10 minutes, until the cheese has melted and the béchamel is bubbling.
For an extra-golden, gratinéed top, switch the oven to broil/grill for 1–2 minutes.
Watch carefully so the cheese doesn’t burn.
6. Serve
Remove from the oven and allow the sandwiches to rest for a couple of minutes.
Cut in half and serve warm while the cheese is still gooey and the béchamel is creamy.
Tips for the Best Croque-Monsieur Gratiné
- Use Gruyère: Its nutty flavor and excellent melting quality make it ideal.
- Don’t make the béchamel too thin; it should be thick enough to stay on top of the sandwich.
- Toasting the bread first helps prevent the sandwich from becoming soggy.
- Use good-quality ham for the best flavor.
- Keep a close eye on the sandwiches under the broiler because the cheese can brown very quickly.
- For an especially rich sandwich, use brioche or pain de mie.
Croque-Madame Variation
To turn this into a Croque-Madame, fry an egg for each sandwich and place it on top just before serving.
The creamy béchamel, melted Gruyère, ham, and runny egg yolk make an especially indulgent combination.
What to Serve With It
Serve your Croque-Monsieur with:
- Simple green salad
- Tomato salad
- French fries
- Pickles or cornichons
- Fresh fruit
- Light vegetable soup
Prep Time: 15 minutes
Cook Time: 15 minutes
Total Time: 30 minutes
Servings: 4 sandwiches
Category: Lunch / Brunch
Cuisine: French
Method: Oven-Baked