1 lb. ground beef
1 c. chopped onion
2 (1 lb. 15 oz.) cans pork and beans
1 (1 lb.) can kidney beans
1 (1 lb.) can butter beans
1 (8 oz.) tomato sauce
1/2 c. catsup
2 tbsp. mustard
1 c. brown sugar
1 tbsp. lemon juice
1 tsp. salt
Pepper

Mix well. Cook in slow cooker, 4-6 hours on low.