Ice palace cake

Put the cream in a heavy-bottomed pan and heat until boiling. Take off the heat and add the white chocolate. Leave for 5 minutes, then stir until smooth. Leave to cool for 1 hour.

Preheat the oven to 160C/140C Fan/Gas 3. Put the mints in a thick plastic bag, then put this bag inside two more bags to reinforce it against splitting. Using a rolling-pin handle, bash the mints until they are finely crushed.

Spread a quarter of the crushed mints over a nonstick baking sheet, and cook for 8-10 minutes, until they have melted and spread out. Remove from the oven and leave to cool. Break into shards and set aside. repeat 3 more times with the rest of the crushed mints.

To make 2 Swiss roll sponges, preheat the oven to 200C/180C Fan/Gas 6. Oil two 37cm x 25cm Swiss roll tins and line with baking paper. Whisk the eggs and sugar for 5 minutes until pale and thick. Sift the flour and baking powder together - repeat 3 times. Add to the egg mixture with the vanilla and water. Fold together. Spoon into the tin and spread evenly. Cook for 18 minutes until golden and the sponge springs back when pressed lightly. Turn out the sponge onto clean baking paper. Peel off and discard the paper liner it was baked on. Roll up the sponge together with the new baking paper. Cool on a rack, then unroll. Discard the paper.

Whisk the cooled white chocolate cream for 2-3 minutes, until it starts to thicken. Chill in the fridge for 30 minutes, then whip again until it's glossy and fluffy but still spreadable.

Set aside two-thirds of the white chocolate cream. Spread the rest on the unrolled sponges. Crush the raspberries with a fork and spread over the cream.

Cut each sponge in half lengthways. Roll up one half and stand on a serving plate, cut-side up. Wrap a second half around the first section, then repeat with the third half.

Roll the remaining half up separately and sit it on top of the larger cake. Push a wooden skewer down through the cakes to secure the top cake onto the lower one.

Spread the remaining white chocolate cream over the cake, to look like jagged snow peaks. Wrap very loosely in clingfilm and chill until ready to serve. Remove the clingfilm and skewer. Push the mint shards into the white chocolate-cream icing to decorate.