Croque Monsieur

Step 1 -Preheat the oven to 400 degrees F.

Step 2 -Melt the butter over low heat in a small saucepan on the stove-top.

Step 3 -Add the flour all at once, stirring with a wooden spoon for 2 minutes.

Step 4 -Slowly pour the hot milk into the butter-flour mixture and cook, whisking constantly, until the sauce is thickened.

Step 5 -Take the saucepan off the heat.

Step 6 -Add the salt, the pepper, the nutmeg, 1/2 cup of the grated Gruyère, and the parmesan.

Step 7 -Stir and set it aside.

Step 8 -Place the bread slices on two baking sheets.

Step 9 -Bake the bread slices for 5 minutes.

Step 10 -Turn each slice and bake until toasted, about 2 minutes.

Step 11 -Lightly brush half the toasted pieces of bread with the mustard.

Step 12 -Add a slice of ham to each of the mustard-topped slices.

Step 13 -Sprinkle the ham with half of the remaining Gruyère cheese.

Step 14 -Top each topped slice of bread with another piece of the toasted bread.

Step 15 -Slather the tops of the sandwiches with the cheese sauce.

Step 16 -Sprinkle the sauce with the remaining Gruyère cheese.

Step 17 -Bake the sandwiches for 5 minutes.

Step 18 -Turn on the broiler and broil until the topping is bubbly and lightly browned, about 3-5 minutes.

Step 19 -Serve hot.