Preheat broiler. In a microwave, melt butter with garlic. Place rolls on a baking sheet, cut side up; brush with butter mixture. Broil 2-3 in. from heat until lightly browned, 2-3 minutes., In a small bowl, mix tuna, mayonnaise and 1 teaspoon dill. Layer roll bottoms with tuna mixture and cheese. Broil until cheese is melted, 1-2 minutes longer. Top with tomato; sprinkle with remaining dill. Replace tops; serve immediately.