There are many kitchen gadgets out there to help with coring and peeling apples, but we prefer to use a sharp knife. This is how to get 16 thin slices from a medium-sized Macintosh apple. Start by standing the apple upright on a wooden cutting board. Cut the apple in half from top to bottom and then in half again to make quarters. Next, carve out the core on each quarter of the apple. Slice each quarter into four slices to give you a total of 16 apple slices.