Put the onion,quartered, and the garlic,chopped, in a food processor and process with several spirts of the processor dial until finely chopped. Add the next 8 ingredients and process on # 3 until well blended. Pour into a large measuring cup. Combine a little sauce with the cornstarch to blend and gradually add to the main sauce. Microwave for 2 minutes on high; stir and repeat. When sauce is thickened, microwave on # 4 for 5 minutes.( You can prepare sauce in a saucepan on the stove element,stirring constantly until sauce thickens and simmering 5 min. )Set sauce aside.

Preheat oven to 375F. Line a large roasting pan with aluminum foil. Put a cookie cooling rack in the pan and place the lamb rib racks on top, fat side up. Cook in the oven for 30 minutes. Turn lamb over and cook another 15 minutes. Baste with sauce and cook for 15 minutes. Turn lamb over and remove as much fat as possible and discard. Baste this side with sauce and cook for 15 minutes. Cook another 20 to 30 minutes, basting every 10 minutes or so, until done to your liking.

Serves 4 people.