In a food processor or blender, combine the aji amarillo paste, minced garlic, soy sauce, red wine vinegar, lime juice, olive oil, ground cumin, dried oregano, smoked paprika, black pepper, salt, and optional chopped cilantro. Process until a smooth paste is formed.

Pat the whole chicken thoroughly dry with paper towels. If you haven't already, spatchcock the chicken by removing the backbone with kitchen shears and flattening it. Alternatively, you can cut the chicken into 8 pieces (2 drumsticks, 2 thighs, 2 wings, 2 breasts).

Place the chicken in a large bowl or a sturdy zip-top bag. Pour the prepared marinade over the chicken, ensuring it is completely coated. Massage the marinade into the chicken, getting under the skin where possible for maximum flavor.

Cover the bowl or seal the bag and refrigerate for at least 4 hours, or preferably overnight (up to 24 hours) for the best flavor penetration.

Preheat your oven to 400°F (200°C). If using a roasting pan, place a rack inside it to allow air circulation around the chicken. This helps achieve crispy skin.

Remove the chicken from the refrigerator at least 30 minutes before roasting to bring it closer to room temperature.

Place the marinated chicken, skin-side up, on the prepared roasting rack. Discard any excess marinade from the bowl.

Roast for 60-75 minutes, or until the internal temperature reaches 165°F (74°C) when a meat thermometer is inserted into the thickest part of the thigh, avoiding the bone. If desired, baste the chicken with melted butter or olive oil halfway through cooking for extra crispiness and flavor.

Once cooked, remove the chicken from the oven and transfer it to a cutting board. Tent loosely with foil and let it rest for 10-15 minutes. This allows the juices to redistribute, ensuring a more tender and flavorful chicken.

Carve the chicken into desired pieces. Serve immediately with traditional sides like aji verde sauce, French fries, and a simple salad.