1 (6 1/2 or 7 oz.) can tuna
1 (4 oz.) c. cubed Swiss or American cheese
1/2 c. chopped celery
1/4 c. mayonnaise
1 tbsp. chopped onion
4 buttered hamburger buns

Combine first 5 ingredients and fill buns with mixture. Wrap in foil and bake in 400 degree oven for 15 minutes. Makes 4 burgers.