White chocolate mousse and rhubarb cake

To make the mousse, whisk cream to stiff peaks. Place in a bowl and reserve in the fridge. Place chocolate in a bowl. Bring a saucepan of water to the boil. Place chocolate over water and remove saucepan from heat. Stand and allow chocolate to slowly melt. Place yolks in a mixer and beat until pale and fluffy. Place 60 grams sugar and water in a small saucepan and stir to dissolve.

Bring to 115C* and pour on to yolks, still whisking. Soften gelatin in cold water and add to hot yolks. Whisk for five minutes. Whisk in chocolate then fold through cream, one third at a time. Place rhubarb and 50 grams sugar in a saucepan. Cook on a low heat until the rhubarb releases some liquid then, stirring regularly, cook on a medium heat until rhubarb starts to "plop".Chill and reserve.

To make the biscuit, pre-heat oven to 150C. Cream butter and remaining sugar. Stir through egg whites and then flour. Trace four 20-centimetre diameter circles on baking paper and spread biscuit batter evenly onto circles. Sprinkle with almonds and bake until golden, about 20 minutes. Allow to cool. Layer biscuit, mousse and rhubarb, starting and ending with biscuit.

*This is known as soft ball stage. If you don't have a thermometer, take a small amount of syrup from the saucepan and place in iced water. If it forms a soft ball, it has reached 115C and is ready.