Croque Madame Muffins

Name: Croque Madame Muffins
Ingredients: * 1 tablespoon of butter; * 1 tablespoon of flour; * 1 cup of milk; * 1/3 teaspoon of freshly grated nutmeg; * 1/2 teaspoon of dijon mustard; * 1/8 teaspoon of cayenne pepper; * 1/4 teaspoon of freshly ground black pepper; * 1/4 teaspoon of salt; * 1/2 cup of grated gruyere cheese, divided; * 2 tablespoon of parmesan cheese; for the muffin:; * 6 slice of white bread, crust removed; * 3 tablespoon of butter, melted; * 3 ounce of deli ham, diced; * 6 egg