- 2 tbsp butter
- 2 tbsp flour
- 2 cups milk
- 1/2 cup grated Gruyere
- 8 slices Gruyere
- 1/2 cup grated Parmesan cheese
- 8 thick slices rustic bread
- 12 slices ham
- dijon mustard
Melt butter in saucepan over medium. Whisk in flour. Add milk, bring to a simmer. Cook until thick, whisking, 5 minutes. Remove from heat and add grates cheeses. Whisk until smooth.
Butter bread, arrange half slices on baking sheet. top each with 2 slices Gruyere, and 3 slices ham. Spread mustard onto rest of bread, place on top of ham.
Preheat broiler, heat a grill pan or skillet over medium. Cook until golden brown and cheese melts, 5 minutes per side. Return to baking sheet. Spoon 1/3 cup sauce over top, broil until golden, 3 mintues.