Season the Chicken: Begin by seasoning the boneless, skinless chicken thighs with fine sea salt on both sides. Allow the chicken to rest for 10-15 minutes at room temperature.

Prepare the Chimichurri Sauce: In a mixing bowl, combine chopped flat-leaf parsley, minced garlic, extra virgin olive oil, red wine vinegar, dried oregano, sea salt, black pepper, and crushed red pepper flakes. Stir well.

Marinate the Chicken: Reserve a portion of the chimichurri sauce for serving later. Pour the remaining chimichurri over the seasoned chicken thighs and refrigerate for 10-15 minutes.

Preheat the Grill: Preheat a grill pan over medium-high heat for about 5 minutes.

Grill the Chicken: Place the marinated chicken thighs onto the hot grill pan. Cook for 6-7 minutes per side or until fully cooked, reaching 165°F.

Let the Chicken Rest: Remove the chicken from the grill and let it rest for about 5 minutes.

Serve and Enjoy: Slice the grilled chicken thighs and drizzle with the reserved chimichurri sauce. Serve with chimichurri rice or grilled vegetables.