In a saucepan over medium heat, melt the butter. Add the flour and continue cooking for 1 minute, stirring constantly. Add the milk and bring to a boil, whisking constantly. Gently simmer for about 5 minutes. Remove from the heat and add the nutmeg. Season with salt and pepper. Set aside.
Waffles and Topping
With the rack in the highest position, preheat the oven’s broiler. Line one baking sheet with aluminum foil.
Place the waffles on the sheet. Top with the ham, folding the slices if needed. Top with the asparagus and the béchamel sauce. Sprinkle with the cheese.
Bake for 2 to 3 minutes or until the cheese is lightly