Start by washing and drying your apples. Slice them using the mandoline, starting from the bottom of the apple and working your way toward the stem. This will create very thin slices that show the beautiful 'star' effect on the inside of the apple. If you don't have a mandoline try to slice the apples as thinly as possible with a sharp knife. If the slices are too thick they won't crisp up nicely.
Brush off any seeds, arrange the slices of apple on a parchment-lined baking sheet and lightly dust the apples with a touch of cinnamon.
Space evenly on a baking sheet, trying not to overlap the edges of the apples.
Place pan into oven and bake for 45 minutes; flip slices and bake for an additional 30 minutes, or until apples are dry and golden brown.