Pick parsley and cilantro leaves from the stems. You can save the stems for stock or discard them.*
Mince the herbs together until very fine.
Mince garlic.
Combine minced parsley, cilantro, olive oil, red wine vinegar, minced garlic, dried oregano, cumin, crushed red pepper, and salt in a small mixing bowl.
Stir to combine and set aside.
Remove chicken thighs from package and pat them dry with a clean paper towel.
In another mixing bowl, combine ¼ cup prepared chimichurri, Greek yogurt, and honey. Stir to combine.
Sprinkle salt and pepper over all sides of each chicken thigh, including underneath the skin. Under the skin on each chicken thigh, add a scoop of the yogurt chimichurri mixture.
Add 4 thighs to a gallon-size zip-top bag and pour the rest of the yogurt marinade in, making sure each thigh is thoroughly coated all over. Seal the bag and let it marinate for at least 2 hours in the refrigerator, or even overnight!**
Preheat your grill to 375℉.
Add the thighs to the hot grill and let them sear and cook for 15 minutes.
Flip the thighs and cook for an additional 15 minutes, or until the chicken temps at least 160℉. Remove the thighs from the grill and cover them on a plate. They will continue to cook as they rest, covered, and will reach 165°F.
Top each chicken thigh with a generous helping of reserved prepared chimichurri sauce and serve.
*If you don’t want to discard the stems from your fresh herbs, you can finely mince them and include them in your chimichurri as well! They’re perfectly safe to eat and still have lots of flavor, but because they contain more fiber than the leaves, they can make the sauce feel a little coarser and less leafy.**If you’re short on time, you can marinate the chicken for just 30 minutes. However, I prefer a 2-hour marinade as this gives the yogurt, garlic, herbs, vinegar, and spices time to season the chicken more deeply. Overnight is even better for bigger flavor!