Preheat oven to 325 degrees. Trim excess fat from ribs. Rub with a mixture of pepper, paprika, and dry mustard. Cut into 6 serving portions and place in a baking pan. Bake for 45 to 60 minutes. Remove pan from oven and pour off fat.
Combine the remaining ingredients and pour over the ribs. Cover and let stand 15 minutes. Return ribs to 350 degree oven and bake, covered, for 1 1/2 hours. Remove cover, baste, and bake for an additional 1/2 hour. Spoon off excess fat before serving.
1 clove garlic, 3 tbsp vinegar, 8 oz tomato sauce, 1/3 cup onion, 1 1/2 tsp chili powder, 1/2 tsp salt, 1/2 tsp oregano, 1/2 cup water