Sometimes I am so grateful for Pinterest and the new recipes it has brought into my life!
This one in particular is so amazing, though it’s not one we’ll eat regularly and after you see it, and the ingredients, you’ll probably understand why!
Melt the butter over low heat in a small saucepan and add the flour all at once, stirring with a wooden spoon for 2 minutes. Slowly pour the hot milk into the butter–flour mixture and cook, whisking constantly, until the sauce is thickened. Off the heat add the salt, pepper, nutmeg, 1/2 cup grated Gruyere, and the Parmesan and set aside.
Halve and toast the croissants, place the slices on 2 baking sheets and bake for 4 minutes. Turn each slice and bake for another 2 minutes, until toasted.
Lightly brush half the croissant with mustard, add a slice of ham to each, and sprinkle with half the remaining Gruyere. Top with another piece of toasted bread. Slather the tops with the cheese sauce, sprinkle with the remaining Gruyere, and bake the sandwiches for 5 minutes. Turn on the broiler and broil for 3 to 5 minutes, or until the topping is bubbly and lightly browned. Serve hot.