Sprinkle lemon pepper seasoning over chicken. Thinly slice zucchini and squash. Heat BBQ or grill plate, spray with a little oil, and cook zucchini and squash in batches until lightly browned. Cook chicken on same grill plate. Whisk lemon juice with crushed garlic in a large bowl. Add cooked vegetables, onion and herbs, toss together. Serve with cooked chicken.