Pour approx. 1 1⁄2 l water and lemon juice into a large bowl. Wash the apples and cut out the core with an apple corer. Slice or cut apples into thin rings (approx. 1 mm thin).
Place in lemon water.
Drain the apples. Spread a thin layer of oil on two oven racks or line two baking trays with baking paper. Place apple rings on top. In a preheated oven (electric cooker: 100 °C/circulating air: 80 °C/gas: see manufacturer) with the oven door slightly open (e.g.
clamp a wooden spoon between them) 4 1⁄2 Dry for 5 hours.
Mix sugar and cinnamon. Melt the dark and milk chocolate coating in a water bath. Dip half of the chips into the couverture and allow to dry. Turn the remaining chips in cinnamon sugar.