Combine the tomato sauce, garlic, oil, onion, Worcestershire sauce, chili powder and vinegar in a small saucepan.2
Heat and stir for 5 minutes.3
Remove ½ cup of the sauce and keep the remainder at a warm temperature, but do not boil.4 Set the Temperature to 375°F/185°C to allow the George Foreman grill to preheat.5
Place the chicken in the grill and spoon ½ of the sauce over each breast. Close the grill and set the Timer to 5 minutes.6 When the Timer beeps, check the chicken with the tip of a knife. If the chicken is not cooked completely through, continue grilling for 1 to 2 minutes.7 Pass the remaining sauce with the grilled chicken.
