Tip half the sugar into the slow cooker and place the gammon on top. Rub over the remaining sugar. Pour in the cider around the gammon. Add the bay leaves and peppercorns. Cover with the lid and cook on high for 4hr. Lift out of slow cooker and discard liquid. If you want to glaze the ham, follow GH Tip below. Serve hot or cold with mash and greens, crusty bread or potato salad and mustard.