Preheat the oven to 150°C and line a 33cm x 28cm tin.
Whisk egg whites to soft peaks.
Add sugars gradually and whisk until stiff and glossy.
Whisk in cornflour and cocoa until combined.
Spoon mixture into the tin and smooth the surface.
Bake for 60 minutes or until a skewer comes out clean.
Whisk cream, icing sugar, and vanilla seeds to soft peaks.
Dust paper with icing sugar and turn the cake onto it.
Peel off the lining paper and trim the long edges.
Spread raspberry purée, cream, and cranberries over the cake.
Roll the meringue using the paper and place it on a plate.
Dust with sugar and cocoa, then serve with raspberries and sauce.