In a mixing bowl, whisk together the Greek yogurt, olive oil, lemon juice, lemon zest, minced garlic, minced ginger, ground cumin, ground coriander, paprika, cayenne pepper, cinnamon, salt, freshly ground black pepper, and chopped cilantro until well combined.

Place the boneless skinless chicken thighs or breasts in a gallon-size resealable freezer bag. Pour the yogurt marinade over the chicken.

Seal the bag while pressing out any excess air and massage the marinade evenly over all pieces of chicken.

Let the chicken marinate in the refrigerator for at least 2 hours. For optimal flavor and tenderness, marinate up to 8 hours for chicken breasts or up to 24 hours for thighs.

Preheat a gas grill to 425°F (220°C).

Clean the grill grates thoroughly, then lightly brush them with oil using a balled-up paper towel held with long tongs to prevent sticking.

Place the marinated chicken on the hot grill. Cook for about 5 to 7 minutes per side, turning once, until the internal temperature reaches 165°F (74°C), measured with an instant-read thermometer in the thickest part of the chicken.

To prevent the chicken exterior from drying out, you can brush the pieces lightly with olive oil halfway through grilling.

Remove the chicken from the grill, let it rest for a few minutes, and garnish with additional chopped cilantro before serving.