1). Spread shelled nuts in a single layer on a baking sheet (no butter or oil needed).
Bake at 275° for 35 minutes or until skins crack.  To remove the skins place the
nuts in a rough towel and rub vigorously until most of the skins are removed.
Roasting at a  lower temperature as instructed above insures a quality rich flavor without the over cooked burned taste.  

Enjoy!

This recipe is more work but is attractive as a gift item.
NOTE: the dark liquid will stain your sink!!! 

Bring two cups of water to a boil in a sauce pan.
Add 3t. baking soda and hazelnuts, boil for 3-5 minutes or until water turns black. 
Drain off black water by pouring water into a colander, run cold water on the nuts to chill. 
Skins should slip off easily between thumb and forefinger. 
Place drained, skinned nuts onto baking sheet and roast as instructed above.