Place the corned meat in a dish of cold water and allow it to soak for 1-2 hours. Place in the refrigerator.
Place the wood chips in water to soak for at least 30 minutes.
Set up your kettle for indirect low fire cooking method. Light the Heatbeads either by using the supplied charcoal baskets or a chimney starter. While the barbecue is heating, prepare the cabbage.
Slice the bacon rashers crosswise into 1cm pieces. Place 1 tablespoon of the butter in a saucepan and cook over medium heat, on the side burner (or stove top) until melted. Add the bacon and the onion and cook until golden. Remove the saucepan from the burner and drain the bacon drippings into a small bowl, reserve the drippings for coating the outside of the cabbage.
Cut a deep cone shaped incision in the bottom of the cabbage to remove the core and create a cavity for the bacon and onion mixture. Add the barbecue sauce to the bacon and onion, stir to combine. Prop the cabbage up by creating an alfoil ring, to help it stand (cavity up), you made need to slice a little off the bottom to create a flat base. Fill the cavity with the bacon mixture and top with the remaining diced butter. Coat the cabbage with the bacon drippings using a basting brush. Season the cabbage with salt and pepper.
Remove the meat from the water and discard the water.
Once the coals are ashed over, separate the baskets using tongs. Place drip trays between the two fires- must be large enough to catch all of the drips. Add half of the wood chips to each side of the coals. Place the cooking grill on the barbecue with the grill handles directly over the fire.
Place the cabbage with the alfoil ring and the meat (fat side up) onto the cooking grill between the two fires. Place the lid on, ensuring the air vents are open.
Cook the meat and cabbage for 1 ½ hours. After 20 minutes of cooking time, pour ½ cup of water over the meat to remove any salt crust. Repeat this process every 20 minutes until the meat is cooked. When cooked the cabbage will be very tender and can be pierced with a skewer. Peel the outside layers off the cabbage, cut into quarters and finely slice. Place cabbage into a bowl and stir to combine the flavours.
Slice the corned beef and serve warm with the barbecued cabbage.