Bar b que Sauce

Heat oil in pan. Dice onion, add to pan. Brown onions over high heat, add garlic, if desired. Stir as needed, so the onion doesn't burn. When onion turns clear, add the following and quickly stir in vinegar, Worcestershire sauce, molasses and mustard. When these have mulled together, stir in catsup and cold water with cornstarch stirred in. Simmer sauce over low heat, for at least ten minutes. Take care it doesn't burn. More water can be added, to thin, or to make more sauce. The corn starch will thicken the sauce as it simmers. This sauce can be used as a marinade for beef, pork or chicken. Remove meat from sauce to BBQ, or bake in sauce in oven at 350'F. Usually marinade enough chicken for 6-8 people in half of this recipe and freeze the other half of the sauce, for another time.