01 - In a large bowl, whisk together Greek yogurt, minced garlic, lemon juice, olive oil, oregano, cumin, smoked paprika, salt, black pepper, and lemon zest until smooth and well combined.
02 - Add chicken breasts to the bowl and turn to coat thoroughly with the marinade. Cover and refrigerate for at least 2 hours, up to 8 hours, to allow flavors to penetrate the meat.
03 - Preheat grill to medium-high heat or preheat oven to 425°F. Prepare a lined baking sheet if using the oven method.
04 - Take chicken out of the marinade, allowing excess to drip off. Discard any leftover marinade—do not reuse.
05 - For grilling: place chicken on the grill and cook for 6–8 minutes per side, or until internal temperature reaches 165°F. For baking: arrange chicken on the prepared baking sheet and bake for 18–22 minutes, or until cooked through.
06 - Let chicken rest for 5 minutes before slicing to retain juices. Garnish with chopped fresh parsley and serve with lemon wedges on the side.