Does anyone know how to cook chestnuts in oven how long what temp.?

You put them on a cookie sheet and when they pop they're done, pop,pop,pop like the song says.

Does anyone know how to cook chestnuts in oven how long what temp.?
Roasted Chestnuts

Before roasting the chestnuts make a cut in the round side of each one to keep them from exploding. Place the chestnuts, cut sides up, on a baking sheet. Roast at 400 degree F until tender, about 20 minutes.

Insert fork through cut in shell to test tenderness. Wrap the hot chestnuts in an old towel squeezing them hard to crush the skins. Set them aside leaving them wrapped for about five minutes.

Bad Teeth