Croque Monsieur

Ingredients

• 1/4 cup unsalted butter
• 1/4 cup all-purpose flour
• 1 1/2 cups whole milk
• Salt and freshly ground black pepper
• 1/4 tsp Dijon mustard
• Dash of ground nutmeg
• 8 thin slices white sandwich bread
• 5 oz good quality ham, about 8 slices
• 6 oz Gruyère cheese, grated (about 2 1/2 cups)
• 1/4 cup freshly grated Parmesan cheese

Instructions

1. Melt butter in a medium saucepan over medium heat. Whisk in flour and cook, stirring constantly, for about 3 minutes.
2. Gradually add milk, stirring well until the mixture is smooth. Cook, stirring, until sauce is thickened.
3. Season with a little bit of salt and pepper. Remove from heat and whisk in mustard and nutmeg. Set aside while you make the sandwiches.
4. Preheat oven to 425°F. Line a baking tray with parchment paper and set aside.
5. Spread each bread slice with a layer of béchamel, spreading it all the way to the edges. Place 4 slices of bread, béchamel side up, on prepared baking sheet.
6. Top each with a piece of ham, a handful of Gruyère, and a sprinkle of Parmesan cheese.
7. Place remaining slices of bread on top, béchamel side up, then top with remaining Gruyère and Parmesan cheese.
8. Bake at 425°F for about 5-6 minutes, until cheese is melted, then turn the oven to broil and broil until the cheese on top is lightly golden, 2-4 minutes.