01 - In a blender or food processor, combine the chili peppers, garlic cloves, red onion, lemon juice, apple cider vinegar, olive oil, smoked paprika, dried oregano, coarse sea salt, black pepper, and brown sugar. Blend until a smooth, vibrant paste forms.
02 - Place the chicken thighs and drumsticks in a large bowl or resealable plastic bag. Pour the marinade over the chicken, massaging it into every piece to ensure thorough, even coating. Cover tightly and refrigerate for at least 2 hours, or ideally overnight for maximum flavor penetration.
03 - Preheat the oven to 400°F or prepare a grill for medium-high heat, ensuring the grates are clean and lightly oiled.
04 - Remove the chicken from the marinade, allowing any excess to drip off. Reserve a small portion of the marinade for basting during cooking. Arrange the pieces on a foil-lined baking tray or directly onto the preheated grill grate.
05 - Cook the chicken for 35 to 40 minutes, turning and basting once or twice with the reserved marinade, until the internal temperature reaches 165°F and the skin is deeply golden, crispy, and lightly charred in spots.
06 - Transfer the chicken to a platter and let it rest for 5 minutes to allow the juices to redistribute. Garnish generously with chopped fresh cilantro or parsley and serve alongside lemon wedges.