Using a paring knife, slit into the shell and the skin down the side of each Chestnuts (16 ounce) and place in a heatproof bowl.
While you slit the chestnuts, bring a kettle or pot of Water (to taste) to a boil.
While you slit the chestnuts, bring a kettle or pot of water to a boil. Once all of the chestnuts are slit and the water has come to a boil, pour the boiling water over the chestnuts and let them soak until the water has come to room temperature for about 30-45 minutes.
Place a 12 inch cast iron skillet into the oven and preheat to 375 degrees F (190 degrees C).
Once the oven is preheated, remove the hot cast iron skillet from the oven and place the soaked chestnuts into the skillet. Return to the oven and roast for 30 minutes.
When finished roasting, remove chestnuts from the oven and cover the pan with a lid or wrap the nuts in a dishcloth to further steam them if they have not all completely opened up. Let them steam for about 10 minutes or more.
Keeping the chestnuts covered so they stay warm, one by one remove each chestnut from their shell and skin.
Eat them warm just as is or use in a recipe. Enjoy!