Dough

1. Prepare two baking trays, fitting them with parchment paper.
2. Chop the hazelnuts into small pieces and put into a deep dish.
3. Cream together the sugar and butter with a hand-mixer until creamy, for about 2 min.
4. Add in the eggs, vanilla bean, salt, flour and baking powder and keep mixing until a homogeneous dough forms.
5. Preheat your oven to 180° C.
6. With a teaspoon, take out a small portion of the dough and roll it between your hands until you have a round ball. Make your hands wet first for easier rolling.
7. Then roll your ball into the chopped hazelnuts until evenly coated.
8. Set it down unto the parchment paper and dent it in the center with your finger.
9. Do this with the whole dough and bake for about 13min on the middle rack.
10. Let them cool completely.

Toffee

1. In a non-stick pan, bring the sugar, heavy cream and butter to a boil.
2. Reduce heat to low and let it cook, stirring constantly, for 5-10 min until it starts to thicken.
3. Fill the toffee into the center of your cookies, working quickly as the toffee will thicken as it cools. Let it set until firm.
4. In a double broiler or electric melting pot, melt the chocolate.
5. Fit your piping bag with a small round tip (Wilton 1,2, or 3 round tip) and scoop the bag over a tall glass.
6. Fill the chocolate into the bag and pipe lines unto your cookies. Let them cool.