This is the great jewish deli tuna melt that I’ve never had. Let’s get right into the good stuff. Challah Tuna Melt You’ll need: challah bread one can of tuna 1/4 cup mayo 1/8 cup chopped celery 1 tablespoon chopped chives fresh ground pepper cheddar/american/colby jack cheese First, mix your tuna. Butter one side of each slice of challah. Place a generous heap of tuna on your challah along with one or two slices of cheese. Grill, covered, in a skillet on medium heat–about two minutes on each side.