Roast the hazelnuts on a tray for 10-15 minutes in the oven. Shake the tray about halfway through to ensure even cooking. Some of the skins may actually look burnt but this is what we want.
Once the hazelnuts are dark brown, immediately wrap them in a kitchen towel and allow them to steam.
Rub the kitchen towel with your hands to peel the nuts. You can also try smashing the tightly wrapped towel against a counter table to help break the skins.
Not all of the hazelnuts will peel perfectly but you can try to roast these ones longer to get the skins off.Let them cool completely, then store in a sealed container for up to 3 months in a cool dark place.
Notes
Use a kitchen towel that you don't mind messing up because it may rip a little after peeling the hazelnuts.If they are difficult to peel, try putting them back in the oven and roast them longer.