Preheat oven to 350°.
Combine honey and mustard in a small bowl. Cut bread in half lengthwise; place on a baking sheet. Spread honey mixture on bottom half of loaf; top with turkey and cheese. Bake at 350° for 5 minutes or until cheese begins to melt.
Arrange watercress and apple slices onto melted cheese; sprinkle with pepper. Cover with top half of loaf, and cut into 4 portions.