* Finely ground the hazelnuts in a food processor. Place the milk in a saucepan over medium heat until hot when bubbles start to appear.
* Stir the hazelnuts into the milk. Turn heat off and set aside to cool.
* Transfer to a bowl and place in the refrigerator for several hours, better if overnight.
* Strain the milk through a fine colander lined with cheesecloth.
* Squeeze the cheesecloth so that all the hazelnut flavored milk is extracted.
* Transfer the milk to a saucepan over medium heat and add the chocolate.
* Beat sugar and egg yolks in a food processor until very fluffy.
* When the chocolate is melted pour the milk chocolate slowly into the eggs with the food processor still running.
* Return the mixture to the saucepan over medium heat.
* Cook stirring constantly for about 8 minutes or until the custard thickens.
* Place the custard into a bowl, and this over a larger container full of aced water. Stir to cool the mixture. Transfer to a refrigerator for at least 2 or 3 hours.
* When the mixture is cold, transfer ti to the ice cream maker and follow the ice cream machine instructions.
* Transfer the ice cream to a container and freeze.