Preheat oven to 400 degrees F.
Heat milk in a small pan until hot, but not boiling. In a separate saucepan, melt butter over low heat. Add flour, stirring until golden brown. Gradually pour the hot milk into the butter and flour mixture and cook, whisking constantly, until you have a creamy thick sauce. Remove from heat and season with salt and pepper to taste. Stir in 1/4 cup grated gruyere and set aside.
Place the bread slices on a baking sheets and bake for 5 minutes. Turn each slice and bake for another 2 minutes, until toasted. Meanwhile, mix dijon with Sweet Wino jam.
Spread half the slices of toasted bread with jam/mustard mixture, add a couple of slices of ham, and sprinkle with half the remaining gruyere. Top with another piece of toasted bread.
Slather the tops with the cheese sauce, sprinkle with the remaining gruyere, and bake for 5 minutes. Turn on the broiler and broil for 3 to 5 minutes, or until the topping is bubbly and lightly browned. Serve immediately.