Wash the limes in hot water and rub dry. Remove lime zest from 2 limes with a zest ripper and lift up. Juice 2 limes. Separate eggs. Put the egg yolks, lime juice, vanillin sugar and sugar in a bowl and whisk with the whisk of the hand mixer for approx. 12 minutes until white and frothy.
Add lime zests. Soak gelatine in cold water, squeeze out and dissolve. Add a little egg mixture to the gelatine. Then add the gelatine to the egg mixture while stirring constantly. Whip the egg whites and cream separately with the whisk of the hand mixer until stiff and fold into the cream.
Pour into glasses and chill for at least 4 hours. Cut the remaining lime into thin slices. Decorate with cranberries and lime slices just before serving.