BARBEQUED HAMBURGERS

2 lbs. hamburger
2 onions
2 c. celery
1/2 green pepper
3/4 c. ketchup
1 can tomato soup
1 can water
2 tbsp. flour
1 1/2 tbsp. prepared mustard
2 tsp. salt
1 1/2 tbsp. chili powder

Brown hamburger; drain off fat. Mix other ingredients in blender and cook until thickened. Add to hamburger and heat thoroughly.