To a blender, add the soy sauce, red wine vinegar, huacatauy or fresh mint, jalapeño, ginger, garlic cloves, cumin, paprika, salt and freshly ground cracked pepper. Blend until very smooth, about 1 minute.
To a large bowl, add the bone-in chicken thighs. And then pour in the soy sauce mixture. Cover the bowl and transfer to the fridge to marinate for at least 2 hours or up to overnight. When you’re ready to grill, remove from the fridge and allow to temper for about 30 minutes.
Meanwhile, preheat your grill for 10 minutes. When you’re ready, brush the grill with neutral oil. To the direct heat, place the chicken, skin side down and cover, cooking for about 5 to 7 minutes, checking on it at the 7 minute mark. Flip if needed, and cook on the opposite side for 2 minutes.
Remove from direct heat and place on a part of the grill that is indirect heat; cook for an additional 15 to 20 minutes, until a thermometer inserted into the thickest part of the thigh reads 165F. Remove from the grill and garnish with cilantro or green onions.