In a small saucepan, mix cornstarch and water until slightly thickened (pours like Pepto Bismol^® antacid). Add small amounts of water or cornstarch to get the right consistency. Add brown sugar, soy sauce, vinegar, garlic, ginger, and pepper. Bring to a boil. Cook until sauce thickens and pours like syrup. Baste meat or veggies with sauce and bake at 375^oF. Baste every 15-20 minutes until tender. Remaining sauce can be served over rice. Makes about 2½ C.