Preheat the oven to 425°F (220°C)
Rinse and dry the chestnuts
Cut an X into the flat side of each chestnut
Place chestnuts on a baking sheet, cut side up
Roast for 20 to 25 minutes
Shake the pan once halfway through
Remove from the oven when the shells curl back
Wrap the hot chestnuts in a clean towel for 5 to 10 minutes
Peel the shells and inner skin while still warm