Steps to Make It

1.Preheat the oven to 425 F.

2.Using a sharp paring knife, make an X-shaped cut on the round side of each chestnut, to keep them from exploding from internal pressure when heated.

3.Arrange them on either a baking rack or a baking sheet.

4. Transfer the chestnuts to the oven and roast them until the skins have pulled back from the cuts and the nutmeats have softened (exactly how long will depend on the chestnuts, but at least 15 to 20 minutes).

Sourced from: https://www.thespruceeats.com/how-to-roast-chestnuts-in-oven-4113870