Dessert sandwich

Cream the butter and sugar until light and fluffy.

Separate the egg yolks and egg whites.

Stir the milk (at room temperature) with egg yolks.

Stieve together

Fold the egg mixture into the butter and sugar mixture, then fold in the sieved dried ingredients.
Whisk the egg whites to soft peak stage and fold through the cake batter without over working.
Spread onto a 60 x 40 cm baking tray lined with a silpat mat
Bake at 180°c for 15 minutes.

Make a crème patissiere

Pour the warm crème patisserie onto the white chocolate and Mycryo cocoa butter.

Blend the mix at 35 °C, then fold through the semi-whipped cream.

Melt the chocolate to 50-55C so it feels hot.

Whisk together to ribbon stage.

Add half the cream to the hot chocolate and mix together with a whisk thoroughly. The mixture should have a shine. (If at this stage the mix has set too quickly the mix can be softened in the microwave).
Gently fold in the rest of the cream with a balloon whisk to avoid separation.

Trim the rich chocolate cake.
Spread one quarter with the prepared Passion Fruit Mousse
Place a quarter of cake on top of the layer sponge 
Repeat with the remaining two quarters sandwiching together with the white chocolate vanilla mousse then allow to set in the fridge
Cut into triangles and serve.