Step 1

Whisk lime juice, olive oil, garlic, lime zest, salt, brown sugar, red pepper flakes, and cumin together in a small bowl. Place chicken in a large plastic bag or a bowl and add lime marinade. Seal the bag or cover the bowl and place in a refrigerator to marinate for 30 minutes to 24 hours.

Step 2

Preheat an outdoor grill for medium-high heat and lightly oil the grate.

Step 3

Place chicken breasts on the preheated grill and cook until no longer pink in the center and skin is golden and lightly charred, about 5 minutes per side. Transfer chicken breasts to a plate and let rest for 5 minutes. Slice and garnish with cilantro.