2. In a small bowl, combine the peanut butter, half of the green onions, soy sauce, vinegar, and cayenne. Gently loosen the skin of the chicken and spread half of the paste between the skin and the meat. Rub the rest of the paste all over the outside of the chicken. Put the remaining green onions, ginger, garlic, and cilantro into the chicken cavity.
3. Roast the chicken, breast side down, in a roasting pan for about 20 minutes. Reduce the oven temperature to 325 degrees and flip the chicken breast side up. Baste with any juices that have accumulated in the pan. Roast for 30 to 40 minutes, until a meat thermometer inserted in the thickest part of the thigh reads 160 to 165 degrees and the juices run clear. Let the bird rest for 10 minutes before carving.