Preheat oven to 180 Deg C (350 Deg F).

Line a baking sheet with parchment paper.

Spread the hazelnuts on the baking sheet and bake for about 15 minutes or until lightly browned and fragrant.

Do turn them in between around 8 minutes.

Once done remove and let it cool.

Rub it between your palms to remove the skin off.

Alternatively you can put all the hazelnuts in a clean towel and gently rub them. This will take the skin off.

Chop the Hazelnuts coarsely

Reduce the oven temperature to 150 Deg C (300 Deg F)

In a food processor or a powerful blender, add in the coarsely chopped chocolate and brown sugar and process until the chocolate is very fine.

In a bowl of electric stand mixer or with a hand mixer beat the eggs and vanilla extract until combined (around 1 min)

Add the chocolate/sugar mixture and combine.

Next add in the flour mixture and beat until it roughly forms a dough, adding in the coarsely chopped hazelnuts in between.

Dust your working surface with flour and with floured hands divide the dough into 2 equal portions.

Transfer the log's into a prepared baking sheets lined with parchment paper.

Bake for 35-40 minutes at 150 Deg C until firm to touch.

Remove from the oven, and let it cool down on a wire rack for 10-15 minutes.

Transfer the cooled logs into a cutting board.

Using a serrated or a sharp knife cut into slices 3/4 inch (around 2 cm) thick.

Arrange the cut slices on a baking sheet.

Bake for 10 minutes.

Turn the slices over and bake again for 10 minutes or until crisp and dry.

Remove from oven and let it cool on wire rack.

This will store in an airtight container for several weeks.

One can even glaze it with chocolate.