Preheat oven to 350 degrees.
Place oil, onion, chopped garlic, cumin cayenne pepper in a heavy saucepan. Cook, stirring over low heat for 5 minutes. Add the remaining ingredients. Simmer for 10 minutes. Remove from heat. Set aside.
Line a roasting pan with foil. Season turkey with salt and pepper. Place in the roasting pan. Spoon 1 cup of the barbecue sauce over turkey. Place in oven. Baste with additional sauce every 20 minutes until roast is done and all sauce is used. Remove any fat. Slice the roast. Serve with the sauce.