Combine pineapple juice, soy sauce, brown sugar, ketchup, chicken broth, ginger, and garlic in a gallon sized ziploc bag. Reserve 1 cup for basting. Add chicken to bag and marinate for at least 4 hours, or overnight.
Heat grill (or grill pan or skillet) to high heat. Slice pineapple into long spears and rub with brown sugar. Cook chicken for 6-8 minutes on each side, if using thighs, 10-15 if using breasts. Add pineapple to grill in the last 10 minutes of cooking, rotating once. Use a pastry brush to baste with reserved marinade several times in the last 5 minutes of cooking.
Serve with rice or quinoa, green onions, and pineapple.