In a medium bowl, whisk together the pureed mango, lime juice, honey, olive oil, minced garlic, ground cumin, chili powder, salt, and pepper. This will be your marinade.
Place the chicken breasts in a large resealable plastic bag or a shallow dish. Pour the marinade over the chicken, ensuring each piece is well coated. Seal the bag or cover the dish and refrigerate for at least 1 hour, or up to 4 hours for maximum flavor.
Preheat your grill to medium-high heat.
Remove the chicken from the marinade, allowing excess marinade to drip off.
Place the chicken on the grill and cook for 6-7 minutes on each side, or until the internal temperature reaches 165°F (75°C) and the chicken has nice grill marks.
Once cooked, remove from the grill and let it rest for 5 minutes.
Slice the grilled chicken and garnish with chopped fresh cilantro before serving.
Notes
Serve the grilled chicken on a platter with lime wedges and extra mango slices for a colorful display.