2 c. leftover cooked ham, chopped
1 1/2 tsp. prepared mustard
2 tsp. vinegar
1/4 c. catsup
1/2 c. tomato paste
1/2 c. hot water
1/3 c. brown sugar

Mix all ingredients except ham. Simmer 1/2 hour on stove. Add ham and heat through. Pour over hamburger buns.