Croque-Monsieur

Ingredients

• 1/4 pound baked ham, such as prosciutto cotto
• 1/4 teaspoon freshly grated nutmeg
• 2 tablespoons unsalted butter
• 1 teaspoon coarse salt
• 3 tablespoons all-purpose flour
• 4 teaspoons Dijon mustard
• Cornichons
• 2 cups grated Gruyere cheese
• 1/2 teaspoon freshly ground black pepper
• 8 slices toasted or grilled country bread
• 2 teaspoons herbes de Provence
• 2 cups whole milk, heated