Trim excess fat from the chicken thighs and pat them dry with paper towels. If pieces are very thick, use a meat mallet to gently flatten to an even 3/4" thickness for even cooking.

Make cilantro marinade

In a blender or food processor add the cilantro leaves, parsley (if using), Greek yogurt, lime juice, olive oil, garlic cloves, jalapeño, ground cumin, smoked paprika, ground coriander, honey, kosher salt, and black pepper. Blend until smooth and vibrant green, scraping down the sides once if needed. The marinade should be a thick, pourable paste; add 1–2 teaspoons of water if it's too thick to blend.

Coat chicken

Place the chicken thighs in a shallow dish or zip-top bag. Pour about two-thirds of the marinade over the chicken, reserve the remaining third for basting/serving. Turn the chicken to fully coat. Press out excess air and refrigerate.

Marinate time

Marinate at room temperature for 20–30 minutes if short on time, or refrigerate for 2–8 hours for deeper flavor. Do not exceed 24 hours (acid in lime and yogurt will begin to break down texture). Remove chicken from the refrigerator 20–30 minutes before cooking to come closer to room temperature.

Cooking & Finish

Preheat pan

Heat a large heavy skillet (cast iron or stainless steel) over medium-high heat until hot, about 2–3 minutes. Add the vegetable oil and swirl to coat the pan.

Sear chicken

Shake off excess marinade from each thigh (but don’t wipe it off entirely). Place the thighs in the hot pan skin-side down (or smooth side down) in a single layer without crowding. Cook 4–5 minutes undisturbed to develop a deep golden crust. Turn and cook the other side 3–5 minutes, reducing heat to medium if the pan gets too hot. Total internal temperature should reach 165°F (74°C). If thighs are thicker, finish in a 375°F (190°C) oven for 5–8 minutes.

Baste & finish

In the last minute of cooking, add the reserved marinade spoonfuls and the butter to the pan and baste the chicken with the pan juices and melted butter for glossy finish and extra flavor. Sprinkle a pinch of red pepper flakes if you want more heat.

Rest

Transfer chicken to a cutting board and let rest 5 minutes to keep juices. This also allows residual carryover cooking to reach final temperature.

Serve

Slice or serve whole, garnish with the reserved fresh cilantro leaves and lime wedges. Spoon any pan juices over the chicken. Serve with rice, warm tortillas, salad, or roasted vegetables.