Preheat the oven to 400˚F.

Sort through the chestnuts and remove any damaged or cracked nuts.

Rinse the chestnuts with water to remove dust and debris, and place them flat side down on a clean kitchen towel.

Cut an X-shaped slit in each chestnut with a sharp or serrated knife.

Place the prepared chestnuts flat side down in a single layer on baking sheets.

Bake in a preheated oven until roasted, about 15 to 20 minutes. The chestnuts are done once they smell nutty, the shell splits open and curls away from the cut opening, and the meat can be pierced easily with a fork.

Once the chestnuts are roasted, remove the baking sheets from the oven. Cover with kitchen towels, and let the nuts cool slightly.

Remove the shells as soon as the chestnuts are cool enough to handle. Peel the outer shell, and rub off the inner brown membrane with your thumbs or a towel.

Enjoy warm chestnuts right away, or store in an airtight container in the refrigerator for up to 3 days.