In a medium bowl, combine 1 cup of unsweetened pineapple juice, ½ cup of soy sauce, ½ cup of brown sugar, ⅓ cup of ketchup, ¼ cup of chicken broth, 2 teaspoons of freshly grated ginger, and 1 ½ teaspoons of minced garlic, whisking together thoroughly.

Set aside 1 cup of the sauce for basting, and combine the remaining sauce with 4 pounds of boneless, skinless chicken thighs in a ziplock bag for marination. Allow it to marinate for at least 3 hours or, for best results, overnight.

Once the marination process is complete, set your grill to medium heat. Cook the chicken with the lid closed for 6-8 minutes per side, or until the chicken is no longer pink and reaches an internal temperature of 165 degrees Fahrenheit. In the last 5 minutes, occasionally baste the chicken with the reserved marinade. If you wish, garnish with sliced green onions before serving.