Lightly grease the base of the slow cooker and sprinkle with the coconut.
Core the apples, leaving the bases intact, then slice the bottom off each one so it sits flat. Make a small incision in the skin around the middle of each apple to allow steam to escape during cooking. Peel off a 1 cm (½ inch) ring from around the top of each apple.
In a bowl, mix together the sugar, raisi