Place onion, garlic, salt, black pepper, pineapple juice, tomato paste, sugar and TTNJ hot sauce in a food processor. Blend well.
Pour marinade over chicken and rub in ensuring all parts of the chicken are covered by the sauce. Seal and refrigerate for 4 - 24 hrs max.
While the chicken is marinating, prepare the burger toppings.
Get fire going and create charcoal for grilling. You don't want to grill over super high flames. Getting the coals hot enough usually takes about an hour.
Transfer chicken to the grill. Cook for 20-25 minutes, turning every few minutes to ensure even cooking. Use a brush to rub on marinade all over the chicken while grilling.
Internal temperature of the chicken should read 73 degrees C when ready.
Assemble toppings and grilled chicken on burger buns, drizzle TTNJ Pineapple Hot Sauce and away you go!