In a large mixing bowl, whisk together soy sauce, hoisin sauce, honey, rice vinegar, sesame oil, five-spice powder, minced garlic, and grated ginger. Stir in red food coloring if desired, then set aside.

Place the chicken thighs into the marinade, ensuring each piece is thoroughly coated. Cover with plastic wrap or transfer to a resealable bag, and refrigerate for a minimum of 2 hours, ideally overnight.

Preheat your grill or oven to 400°F about 20 minutes before cooking, lightly oiling the grates if grilling.

Remove chicken from the refrigerator, let it come to room temperature for 10 minutes, and then shake off excess marinade. Cook for 25-30 minutes, turning occasionally and basting with reserved marinade.

Let the chicken rest for about 5 minutes after cooking. Slice and garnish with green onions before serving.