When I do the pork ribs with it, I marinade them in the powder and some cold water or orange juice, not loads of liquid but enough to cover the meat in a dish, then either put them in the slow cooker or a big pot, add sliced onions and garlic.
They come out well in the oven too, which would probably be best for pork belly. Just put the pork and liquid in a deep oven tray, arrange the onion slices over the top, swoosh it a bit so the liquid covers the lot and roast them slowly.