INGREDIENTS
1 tbsp
unsalted butter
1 1/2 tbsp
all-purpose flour
1 cup
whole milk, heated
1 tsp
coarse salt
1/2 tsp
freshly ground black pepper
freshly grated nutmeg
2 cups
shredded Gruyere cheese, divided
8
slices toasted or grilled country bread, sliced 1/4 inch thick
4 tsp
Dijon mustard
1/4 lb
sliced baked ham, such as prosciutto cotto or jamon royale
herbes de Provence
Cornichons, for serving