100 g of hazelnut paste (if you can't find it, you have to blend 100 g of toasted hazelnuts until you obtain a paste; with a good blender you have to blend until the hazelnuts release their oil and turn into a paste)
(Optional hazelnuts for decoration)
PROCEDURE
Whip the very cold fresh cream with an electric whisk (or a stand mixer with a whisk).
Add the hazelnut paste and mix.
Add the condensed milk and mix again.
Pour into a freezer-safe container. You can sprinkle some shelled and chopped hazelnuts on top.
Place in the freezer for at least 4 hours.
Remove it from the freezer a few minutes before eating it so that it becomes super creamy again.