The chicken can marinate up to 2 days ahead, covered and refrigerated.
To marinate the chicken:
In a large bowl, mix the hoisin sauce, honey, soy sauce, garlic, and ginger to blend.
Using a sharp knife, score the chicken all over. Add the chicken to the marinade and toss to coat. Cover and refrigerate for at least 1 hour but preferably overnight.
To cook the chicken:
Position your oven rack 8 to 10 inches from the heating source and preheat the broiler. Line a large rimmed baking sheet with heavy-duty foil.
Transfer the chicken and marinade to the baking sheet and broil for 15 minutes, turning often and watching closely, or until the chicken is cooked through and the marinade glazes the chicken.
To serve:
Transfer the chicken to plates. Sprinkle with the sesame seeds, garnish with cilantro sprigs, and serve.
