In a small saucepan over medium heat, melt the butter. Add the flour and cook for 30 seconds. Stir in the milk slowly, whisking away any lumps. Cook for about 10 minutes, until thickened. Remove from heat and add the cheese, sherry, salt, red pepper, onion powder, and diced drained pimentos. Stir until melted and combined. Add the fresh parsley.
Preheat the broiler. Place a layer of aluminum foil on a baking sheet. Arrange toast slices on sheet. Top with turkey and cheese sauce. Add a slice of tomato, bacon crumbs, and sprinkle panko across each. Broil until panko crumbs have browned and cheese sauce begins to bubble.