Use a mandoline slicer or knife to cut the apples into thin slices. Remove the seeds.
In a small bowl, mix together brown sugar, ground cinnamon, and ground cardamom.
Put the apples on a parchment-covered baking sheet. Sprinkle with half of the cinnamon sugar mixture.
Bake at 220°F for 1 hour and 30 minutes.
Remove from the oven, flip the apple slices over, and sprinkle with the remaining cinnamon sugar mixture. Return the pans to the oven, rotating the pan from the top rack to the bottom rack.
Bake at 220°F for 1 hour and 30 minutes. Remove a couple of baked apple chips and let them cool on a plate on the counter for a couple of minutes to see if they get crispy. If so, you are done. If not, continue baking until the apple chips feel dry to the touch and crisp up within a couple of minutes of cooling.
Store in an airtight container for up to one week.