Soak gelatine in cold water. Cut the vanilla pod open lengthwise and scrape the pulp into the milk. Add the vanilla pod and bring the milk to the boil. Stir egg yolk and sugar until creamy. Gradually stir the hot milk into the egg yolk.
Return everything to the pot and heat over medium heat while stirring until the cream thickens. Remove from the heat immediately. Squeeze the gelatine well and stir into the hot cream. Pour through a sieve into a bowl.
Place in a cold water bath and stir from time to time. In the meantime whip cream until stiff. When the cream is cold and begins to gel, stir in the cream and distribute the cream in moulds. Put in a cool place for 1-2 hours.
For the sauce, dissolve coffee in 2 tablespoons of boiling water. Let it cool down a bit, stir in cream and nougat liqueur. Turn the vanilla cream onto plates. Pour sauce around the cream. Use a peeler to slice shavings of the mocha chocolate directly onto the plates.