Beat egg yolks and sugar until thick and creamy.
Combine cocoa powder with 250ml hot water and add oil and essence. Mix well and add to the egg mixture and the sifted flour, Maizena, salt and baking powder.
Beat egg whites until soft peaks form and gently fold into the above mixture. Pour into two greased and lined 23cm-diameter, spring-form cake tins and bake in a preheated oven for 30 minutes at 180 ºC.
Cool, then slice each cake in half horizontally.
Mix Maizena with 50ml milk until smooth. Heat remaining milk, coffee powder, sugar and essence until just before boiling point.
Add Maizena mixture and stir over medium heat until thick and smooth.
Set aside to cool completely.
Beat the butter until light, then mix it into the cold coffee cream.
Heat cream until just before boiling point.
Add chocolate and coffee powder and mix until smooth. Refrigerate until cold, then
beat until thick.
Spread caramel filling on top of each cake layer and stack layers on top of each other.
Cover top and sides of cake with the icing and decorate with strawberries, white-chocolate curls and crumbled Flake pieces.