1. Preheat the oven to 180°C. For the cupcakes, cream the butter and sugar together in a large bowl using a hand mixer until light and fluffy.
2. Beat the eggs together, then gradually add the eggs to the butter and sugar mixture, beating well after each addition. Sift the flour and fold it in, beating until well mixed, then beat in the crème fraîche, milk and vanilla.
3. Divide the mixture between a 12-hole cake tin lined with plain paper cases, then place in the oven and cook for 20 to 25 mins, until risen and lightly golden. Remove from the oven and leave to cool slightly, then remove from cake tin and leave to cool completely on a wire rack.
4. For the icing, Put the butter in a mixing bowl and beat until soft. Gradually sieve in the icing sugar, beating well. Add a few drops of vanilla essence. Mix together and spoon onto cakes as required.
5. Peel the paper cases off the cakes and slot into the ice-cream cones. Pipe or spread the icing on top and add decorations.