With the rack in the middle position, preheat the oven to 100 °C (200 °F). Line two baking sheets with parchment paper.
Ask your parents to cut the apple into thin slices, using a mandoline. Spread them on the baking sheets. With a sieve, dust the apple slices with the icing sugar.
Dry in the oven for 30 minutes. Flip the slices and bake again for 1 hour to 1 hour and 30 minutes. To find out if they are sufficiently dry, remove one from the oven and let cool for 2 minutes on the counter. If it is not completely dry, it will still be soft.
For this recipe, it is imperative that you use parchment paper on your baking sheet because a silicone mat would keep too much moisture and prevent the apples from drying.
Recipes with the "Healthy Pick" stamp have been evaluated by a registered dietitian member of the Ordre professionnel des diététistes du Québec.