Proceedings
Heat 60 g of sugar until it caramelises. Add the coarsely chopped walnuts and keep on the heat for a few minutes. Spread the mixture on a large serving plate and let it cool. Once cold, finely chop the walnut brittle.
In a bain-marie, place the egg yolks and 40 g of sugar. Melt the chocolate in a bain-marie and add it to the mixture, then let it cool. Then add the chopped brittle and the whipped cream.
Pour into individual moulds and place in the freezer for at least 2 hours.
For the sauce, bring the milk to a boil with the remaining sugar, flavour with the vanilla and let it rest. Add one egg yolk and cook until thickened.
Serve the semifreddo moulds on a bed of vanilla sauce.