Cut fresh-cooked beef's tongue or calf's tongue into dice. Have ready peeled perfectly round smooth tomatoes, take out the core and scoop out the seeds. Fill each tomato with the cubes of tongue, sprinkle over a teaspoonful of lemon juice and a little salt and pepper. Stand these on nests of lettuce leaves, put on top of each a large tablespoonful of mayonnaise. Dust thickly with paprika and serve one to each person.