Step 1 In a zip-top plastic bag, combine chicken and vinaigrette. Refrigerate 1 hour (or up to 12 hours). Preheat grill. In large bowl, toss zucchini, tomatoes, and precooked potatoes with oil and season with salt and pepper. Put vegetables in grill wok or grill basket and grill 10 minutes. Add chicken to grill and cook until chicken is done and vegetables are tender, about another 5-10 minutes. Step 2 Transfer chicken to a cutting board and let rest. Toss vegetables with spinach and divide among plates. Slice chicken. Serve chicken on top of salad, with lemon wedges.