In a small bowl stir together honey and mustard. Slice tomato lengthwise. Arrange bread on a baking sheet and toast under broiler until golden on one side. Turn bread over and spread honey mustard on untoasted sides. Sprinkle Cheddar over honey mustard and broil until cheese is melted. Arrange tomato, turkey, and radicchio between melted Cheddar toasts, seasoning with salt and pepper.
