1. Preheat grill to 300° to 350° (medium) heat. Sprinkle chicken with salt and pepper. Combine cheese and next 3 ingredients. Brush chicken with cheese mixture.
2. Toss zucchini, onion, and bell pepper in olive oil.
3. Grill chicken and vegetable mixture at the same time, covered with grill lid. Grill chicken 7 to 10 minutes on each side or until done. Grill vegetable mixture 2 to 3 minutes or until crisp-tender. Chop vegetable mixture, and toss with basil. Add salt and pepper to taste. Serve vegetable mixture with grilled chicken.