Begin by placing the whole chicken, breast-side down, on the preparation surface. Using kitchen shears, remove the backbone by cutting up from the tailbone to the neck on both sides. Open the bird, remove the breastbone and wishbone. Make small cuts on both sides below the thighs to tuck the wings under so you have a flattened "spatchcock" chicken.
To a small saucepan, add 1 cup water, the salt, sugar, bay leaves and garlic cloves. Bring to a simmer to dissolve the salt and sugar. Once at a simmer, turn off the heat and add the ice. Once the liquid is cool, place into a resealable bag over a bowl and add the chicken to the brine, making sure it is completely submersed. Allow to brine in the fridge for 1 hour.
In a small saucepot over medium-low heat, combine the pineapple juice, ketchup, soy sauce and sherry vinegar. Once the liquid simmers, whisk in the brown sugar and ginger. Continue to simmer until the liquid begins to thicken, about 5 minutes.
Remove from the heat and let stand (or prepare ahead and refrigerate until ready for use). Once ready for use, reserve about a cup to serve.
Preheat a grill to medium heat.
Remove the chicken from the brine and pat dry. Thoroughly mix the garlic powder, salt, paprika, cayenne, onion powder, cumin and some black pepper together in a small bowl. Coat the chicken with the dry rub, making sure to sprinkle well inside the cavity.
Lay the chicken flat on the preparation surface, making a neat, rectangular package with the thighs tucked next to the breasts and the wings inserted into the slits.
Secure the chicken in a medium rectangular wire-mesh grilling basket and set over an open grill flame. Char with the breast side down first, 7 to 8 minutes. Turn once and continue to grill, bone-side down for another 15 minutes.
Continue to turn as it cooks so it doesn't burn and it replicates the Huli Huli machine cooking process. Squeeze the lemon juice over the chicken as you turn it. Finish by alternating sides until the chicken is thoroughly browned, the skin is crispy and a digital instant-read thermometer tucked under the breast confirms the internal temperature is 165 degrees F. The total cook time will be 35 to 40 minutes. With a heat-resistant silicone pastry brush, glaze the chicken with the Huli Huli sauce the last 5 minutes.
Remove from the basket and allow the chicken to rest for 6 to 8 minutes.
Carve the chicken into breasts, thighs and wings. Arrange on a large serving dish alongside the reserved Huli Huli sauce.
