Wash apples well. Pat dry. No need to peel unless you want skinless chips.

Preheat your oven to 95 °C (about 200 °F). Line a baking tray with parchment paper.

Slice the apples very thin — about 3 mm thick — using a sharp knife or mandoline. If cores bother you, remove them; otherwise you can leave the rings whole.

Arrange apple slices in a single layer on the lined tray. They can touch but should not overlap.

Lightly sprinkle ground cinnamon over the apple slices (optional). This gives a gentle warm flavour without added sugar.

Bake in preheated oven for 1 hour. Then remove tray, flip every slice gently, and return tray to oven.

Bake for another 1 hour (total ~2 hours). After baking, turn off oven and leave the tray inside with door slightly ajar until chips cool completely — this helps them crisp up fully.

Once completely cooled, transfer apple chips into an airtight container. Store at room temperature for up to 5–7 days.