For the apple chips, preheat the oven to 225 degrees F. Line one sheet pan with parchment. Slice the apple 1/8-inch or thinner using a mandolin. Place the apple slices in a single layer on the prepared sheet pan. Bake the apples for 1-1/2 hours until they are dried and brown. Set aside to cool.

For the donuts, preheat the oven to 350 degrees F. Grease a 6-cup donut pan with non-stick cooking spray. In the bowl of a stand mixer fitted with the paddle attachment, beat the oil, eggs, granulated sugar, applesauce, vanilla extract, cinnamon, salt and baking powder until smooth. Fold in the flour.

Transfer the batter to a piping bag or a Ziploc bag with a corner cut off, and pipe the batter into the pan. Bake for 10-12 minutes until a toothpick inserted into a donut comes out clean. Wait 3 minutes before carefully removing the donuts from the pan. In a small bowl, combine the cinnamon and granulated sugar and coat the donuts. Transfer them to a wire rack to cool. Bake the remaining batter in the donut pan.

For the glaze, whisk together the confectioners’ sugar, maple syrup, salt and 2 teaspoons milk. The glaze should have a pourable consistency. If not, add more milk, 1 teaspoon at a time. Dip the tops of the donuts into the icing letting the excess drip back into the bowl. Top with apple chips. Let set for 1 hour before serving.