Place 1 cup hazelnuts in an oven safe dish and roast for 20 minutes. Transfer to a towel and rub away as many skins as you can.
In a bowl, cover the hazelnuts with water. Transfer to a sieve and shake out the water.
In another bowl, combine the 1/2 cup confectioners sugar, 1/2 teaspoon cayenne pepper, 1/2 teaspoon cinnamon, and 1 teaspoon Kosher salt.
Add the hazelnuts and toss. Transfer to a sieve to shake off the excess coating.
Arrange the hazelnuts on a parchment paper lined baking sheet and bake for 10 to 12 minutes, until the sugar is lightly caramelized and the hazelnuts are golden.