- For cake: Line base of two 16 cm round cake tins with greaseproof paper and brush the sides with softened butter. Place oven rack in middle position and preheat oven to 160。C.
- Mix butter, brown sugar, white sugar, thick caramel sauce, and vanilla essence together in a mixing bowl. Beat with a wooden spoon until well mixed before stirring in the eggs. Finally, add Kimball Mayonnaise.
- Add 1/3 of the sifted flour mixture and mix by hand until combined. Add 1/3 of the cocoa mixture and stir in. Continue adding flour and cocoa mixture alternately until both are used up. Transfer batter into prepared tins and bake in preheated oven for 30 – 35 minutes. Test for doneness by inserting a skewer in the centre of the cake – if it comes out clean (without sticky crumbs clinging to it), the cake is done. Cool cake in tin for 10 minutes before gently loosening cake around the edges with a palette knife. Upturn to cool on a wire rack. Split each cooled cake horizontally, making 4 layers.
- For frosting: Cream butter and half the icing sugar in a mixing bowl until mixture is smooth and creamy. Add remaining icing sugar and Kimball Mayonnaise and continue beating on low speed until frosting is fluffy. Avoid over-beating. Sandwich cake layers with frosting and either spread frosting or pipe rosettes on the top of the cake.