Hazelnuts and Brazil nuts are best toasted rather than blanched before skinning. Here, hazelnuts are toasted in the oven, but if you like you can toast them by dry-frying them on top of the stove. Put them in a non-stick, heavy frying pan and stir over a low heat until lightly toasted on all sides, 2—4 minutes.
Spread the nuts evenly on a baking sheet and roast at 175°C for 10 minutes, shaking the sheet occasionally.
Wrap the roasted nuts in a tea towel to steam for a few minutes, then rub to remove the skins.