Combine ham, Hellmann's® Real Whipped Tangy Dressing, relish and onion in medium bowl.
Spread bread, if desired, with additional Dressing. Arrange 4 bread slices on aluminum-foil-lined broiler pan. Evenly spread bread with ham salad, then top with cheese. Broil 1 minute or until cheese is melted.
Top with lettuce and remaining bread.
*Hellmann’s® Real Whipped Tangy Dressing is only available in the Midwest and Central regions (ND, SD, NE, KS, OK, TX, MN, IA, MO, AR, LA, WI, IL, IN, OH, MI, KY, TN).
*Can be substituted with Hellmann's® or Best Foods® Real Mayonnaise.