Method

1. To make the mousse melt the white chocolate over a Bain Marie.
2. Whilst this is melting bring cream and milk to boil, cool slightly and whisk in the gelatine granules until thoroughly combined. Cool for 5 mins then add to white chocolate Mix and set for 2 hours.
3. Turn oven on to 170C and line a baking tray with grease proof paper and grease with butter.
4. When the cake is cooked have a large piece of greaseproof paper sprinkled in caster sugar ready to turn the sponge into.
5. To make the sponge whisk the 3 egg yolks with 50g icing sugar until double in size and light and fluffy.
6. Combine in the egg mixture with the sifted flours and lemon zest.
7. Whisk the egg whites until soft peaks and add remaining icing sugar whisk to soft peaks again.
8. Take a 1/3rd of the meringue mixture and combine into the egg mix. Fold the other 2/3rds in gently taking care not to over mix keeping its light fluffy texture.
9. Put mix in baking tray smoothing over with a pallet knife so the surface is even and bake for 10mins.
10. Gently remove cake onto grease proof caster sugar paper. Whilst warm roll the sponge into the roulade taking care not to crack the surface.
11. Allow to cool completely.
12. Roll roulade out and add a layer of lemon curd.
13. Now add the white chocolate mousse which should be pliable and easy to mould on top of the lemon curd layer.
14. Add another layer of lemon curd and roll back into the roulade shape.
15. Finish off with whipped double cream piped down the centre, blackberries, white chocolate shards and coarsely ground pistachio nuts.