Soak gelatine in cold water. Whisk the egg yolks, sugar, vanillin sugar and salt with the whisk of the hand mixer until thick and creamy white (approx. 12 minutes). Add lemon zest and rum and stir well. Squeeze the gelatine and melt in a small saucepan over low heat. Remove from the heat and stir until droplets run into the rum egg mixture. Chill for 6-8 minutes until the cream begins to form streaks (begins to gel).
In the meantime, whisk the cream with the whisk of the hand mixer until stiff. Fold into the gelling cream in portions. Pour immediately into four dessert glasses and chill for about 2 hours. Dust with cocoa. Decorate with dessert decoration and mint