1 c. chopped onion
1 1/2 c. catsup
1 1/2 c. tomato sauce
1/2 c. vinegar
1 c. water
6 tbsp. brown sugar
2 tbsp. mustard
2 tbsp. Worcestershire sauce

Combine above ingredients in saucepan and simmer 10 minutes. Place some in bottom of pan; place precooked ribs on sauce. Cover ribs with remaining sauce. Cover ribs and bake at 350 degrees for 2 hours.