Kick the tires and light the fires to 350 degrees.
First, roast your hazelnuts to bring out their flavor. Place them on an ungreased baking sheet and roast in your 350 degree oven for about 10-12 minutes. Every couple of minutes, open the oven, shake the sheet and roll them around so they don't burn.
With a mixer, blend the butter and sugar until creamy and light.
Then whip in the eggs and vanilla, mixing again until the batter is light and airy.
Blend in your flour/baking soda mix.
By now the hazelnuts should be done, take them out of the oven and transfer to a plate. To take most of the skins off, rub a clean tea towel over them, until most of the skins come off. If you leave some on, it's perfectly fine. Place them in a sturdy bag and crush them into tinier pieces.
Add in the chocolate chunks and the nuts, and stir until just blended.
Drop by tablespoonful onto parchment lined sheets.
Bake for 9-10 minutes and let cool on the sheets. They will be soft and chewy and will fall apart if you move them too soon to a rack. When they are ready, move them to a rack to fully cool off.