In a large bowl, whip the cream until it's almost fully whipped (stiff peaks). Don't over mix at this step.
200 ml liquid whipping cream/heavy cream
Add the condensed milk and Nutella and whip until fully combined and the cream is fully whipped and stable. Fold the chopped hazelnuts in the ice cream using a silicone spatula.
160 ml condensed milk, 120 grams Nutella, 25 grams chopped hazelnuts
Transfer the prepared ice cream to a bowl, then top with a few dollops of the remaining Nutella and crunchy wafers and swirl it using a spatula or butter knife. Free the ice cream for at least 8 hours, or overnight.
20 grams Nutella, 20 grams crunchy wafer
Make the chocolate shell: Melt the chocolate and mix it with oil and chopped hazelnuts.
50 grams milk chocolate (for chocolate shell), 5 ml neutral oil (for chocolate shell), 20 grams chopped hazelnuts (for chocolate shell)
While serving, top it with the chocolate shell topping, let it set, crack through and enjoy.