In a mixing bowl, combine plain Greek yogurt, olive oil, lemon juice, ground cumin, smoked paprika, ground coriander, garlic powder, salt, and black pepper. Stir until well blended, then add the boneless, skinless chicken thighs, ensuring they are thoroughly coated. Cover the bowl and marinate for at least 1 hour in the refrigerator for optimal flavor, although overnight is ideal.

Preheat the oven to 425°F (220°C). Line a baking tray with parchment paper or aluminum foil.

Once the oven is preheated, arrange the chicken thighs in a single layer on the lined baking tray. Bake for 30-35 minutes, flipping halfway through, until the chicken reaches an internal temperature of 165°F (74°C).

For extra crispiness, broil for 2-3 minutes after baking.

For grilling, preheat your grill to medium-high heat. Grill the marinated chicken for 5-6 minutes on each side, ensuring it reaches an internal temperature of 165°F (74°C).

Let the chicken rest for about 5 minutes before slicing thinly against the grain.