Croque Monsieur

This recipe combines

Béchamel Cheese Sauce

A ham and cheese sandwich, baked under white sauce and browned cheese until the top bubbles and turns golden. The white sauce is a béchamel — milk thickened with a butter-and-flour roux — and this page includes it so you don't have to jump to another recipe. Classically the sandwich uses Mornay (béchamel with cheese melted in), but plain béchamel under sliced Swiss is what I usually reach for. Add a fried egg on top and it becomes a Croque Madame. The béchamel and cheese sauce also stand on their own.

Serves 2

Ingredients

For the béchamel (½ batch)

• 1½ tablespoons butter
• 1½ tablespoons flour
• 1 cup milk, warmed
• Salt, pepper, and a pinch of nutmeg

For the sandwiches

• 4 slices sandwich bread
• 2 teaspoons Dijon mustard, or to taste
• 4 slices ham
• 6–8 slices Swiss cheese, enough for 1 slice inside each sandwich and 2–3 slices on top

Shortcut: skip the béchamel and spread 2 tablespoons sour cream over the top of each sandwich before the cheese. Classical version: replace the béchamel with ½ batch cheese sauce (Mornay).

Roasting & Baking

Roasted Chicken Thighs Pan-Roasted Hot Wings Pan-Roasted Teriyaki Wings Roasted Pork Tenderloin Roasted Potatoes Roasted Ratatouille Cauliflower Gratin Potatoes au Gratin Baked Potatoes Twice-Baked Potatoes Mac and Cheese Lasagna Spaghetti and Meatballs

Frying in the Oven→

Method

Make the béchamel

Preheat the oven to 425°F (or preheat the broiler if finishing that way). Make a half batch of béchamel: Melt the butter in a saucepan over medium heat, whisk in the flour, and cook, stirring constantly, for 1–2 minutes, until the raw flour smell cooks off — this is your roux. Slowly whisk in the warm milk, a little at a time at first, whisking out any lumps before adding more. Continue cooking, whisking often, until the sauce thickens enough to coat the back of a spoon, 5–7 minutes, then season with salt, pepper, and a pinch of nutmeg.

Assemble the sandwiches

Spread each slice of bread lightly with Dijon and build two sandwiches with the ham and 1 slice of Swiss inside each. Place the sandwiches on a baking sheet and spoon béchamel over the top of each, then lay 2–3 slices of Swiss over each sandwich, letting the cheese overhang the edge by about ⅓ inch so it melts down the sides.

Bake

Bake 10–12 minutes, until the cheese is melted, bubbling, and golden, finishing under the broiler for the last minute or two if you'd like more color. Serve hot, ideally with a Simple Bistro Salad.

The assembled sandwiches, topped with cheese overhanging the edges, just before baking.