In a mixing bowl, combine the honey, balsamic vinegar, olive oil, lime juice, crushed garlic, pesto, and crushed red pepper flakes. Whisk until well combined.
Place the chicken cutlets in a large resealable bag or a shallow dish. Pour half of the marinade over the chicken, ensuring it’s well coated. Seal the bag or cover the dish and refrigerate for at least 30 minutes (or up to 2 hours).
While the chicken is marinating, prepare your vegetables. Trim the tough ends off the asparagus, slice the zucchini into 1/4-inch thick rounds, and slice the red bell pepper into strips. Drizzle with olive oil, salt, and pepper.
Preheat your grill to medium-high heat. Spray the grill grates with olive oil cooking spray to prevent sticking.
Remove the chicken from the marinade, letting any excess drip off. Place the chicken on the grill and cook for about 4-5 minutes on each side, or until the internal temperature reaches 165°F.
Once the chicken is nearly done, add the prepared vegetables to the grill. Grill for about 5-7 minutes, turning occasionally, until they are tender and have nice grill marks.
Remove the chicken and vegetables from the grill. Let the chicken rest for a few minutes before slicing. Serve alongside the colorful vegetables and drizzle with the remaining marinade.