PREPPING THE DUCK
Remove the giblets, neck, and sauce packet from the duck’s cavity.
Starting on the cavity side, gently work your fingers under the skin to separate the skin and flesh.
Bring a large pot of water to a boil. Set the duck on a rack in the sink and ladle the hot water over the duck to tighten the skin, flipping it halfway through the process.
Prick the skin of the duck all over with the tip of a paring knife or metal skewer to help the fat drain more easily.
Combine the soy sauce, rice wine vinegar, and honey in a microwave safe bowl and microwave on high for 15 seconds to liquefy the honey. Stir well to combine the ingredients. Brush the mixture all over the duck.
Combine the salt and baking powder in a small bowl. Mix well and sprinkle the mixture over the entire duck.
Refrigerate the duck uncovered on an elevated rack for at least six hours and up to overnight so that the skin can air dry.
PREPPING THE GRILL
Place a disposable aluminum roasting pan in the center of the grill’s charcoal grate to avoid flare-ups from dripping duck fat. Arrange hot briquets on both sides of the pan. Adjust the grill vents to bring the temperature to about 325°F. Add 2 to 3 chunks of your favorite smoking wood to the charcoal for flavor. If you’re using a gas grill, remove the main cooking grate and place a disposable aluminum pan on one side of the grill directly on top of the burner covers. Replace the main cooking grates and adjust the temperature knobs so that the side containing the aluminum pan (the indirect side) is off and the other side is heated enough to maintain a temperature of approximately 325°F on the indirect side.
GRILLING THE DUCK
Place the duck breast side up directly above the aluminum pan. Set the lid on the grill with the top vent fully open.
Allow the duck to roast for approximately 2 1/2 hours until the skin is golden brown and crispy and the internal temperature of the breast has reached 165°F.
SERVING THE DUCK
Remove the duck from the grill. Wrap the pancakes in a layer of moist paper towels and microwave for 15 seconds to warm them and to make them easier to separate. Thinly slice the duck and serve along with the pancakes, hoisin sauce, and green onion.