Preheat the broiler to high heat. Start by slicing two thick slices of bread, about 1” thick, then slice one of them in half on a bias from corner to corner.
Next, toast the bread until golden brown and place the square slice of bread in the center of a pan or on a sheet tray lined with parchment paper with the triangle slices on either side of the square.
Place thick sliced turkey on top of the toasted square. Generously pour ¼ of the mornay sauce on top of the turkey, completely covering it. You can also cover the triangle slices of toast as well.
Sprinkle 2 tablespoons of parmigiana Reggiano on top of the cheese sauce. Place the pan or tray on the middle rack in the oven with the broiler on high until the sauce is lightly browned.
Place 2 oven-sliced oven-roasted tomatoes on top of the sandwich along with the 2 slices of bacon crisscrossed on top of that. Garnish with more finely grated parmigiana, paprika, and fresh parsley.