Like all great show-stopper bakes, this cake requires some time and commitment to get the sponge colours and layers just so, and to pipe the icing in a way that is neat and level. Of course, if you don’t have the patience for this simple ‘petal’ icing technique, then just spread your cake with the frosting, pile some blueberries on top and dust with icing sugar.
Cream together the butter and caster sugar until light and fluffy. You can do this for 5 minutes in a stand mixer or using a hand-held electric whisk. You can also do this by hand, but it takes about 10 minutes and lots of elbow grease! Add four eggs and half of the flour to the creamed butter and sugar and beat well together. Then add the remaining eggs and the rest of the flour and salt and beat well again until well combined.
Divide the mixture into five small bowls, weighing each one to make sure it is even (you need about 350g per bowl). Now it is time to colour the ombre sponges, so they range from dark to light. I like to start with the darkest one first and get that a good purple colour. Remember that the purple will go a little darker when it bakes but not too much. Keep the lightest bowl as white batter, so you only need to colour four of the bowls. When you are happy with your colours, spoon the batters into your lined tins, using a spatula to scrape the bowls so you don’t waste a drop of the batter. Spread the mixture evenly in the tins and bake the cakes in the oven (in batches if necessary) for 25–30 minutes, or until a skewer inserted into the centre of each cake comes out clean. Once the cakes are baked, gently turn them out onto wire racks to cool and peel off the baking parchment.
While the cakes are cooling make the frosting. Put the butter into the stand mixer and beat well until very soft and light. Add the icing sugar in four goes, beating well between each addition. Cover the mixer with a tea towel so that the icing sugar does not fly everywhere.
Once the butter and the icing sugar are well combined, add the cream cheese and vanilla and then beat until just combined. Place
Once the cakes have cooled and the frostings have firmed a little, put all five cakes on the work surface, flat-sides up. Cut off the end of each piping bag, making sure each hole is the same size. Smear a splodge of the white frosting on your cake stand or plate to secure the white sponge. Spread a thin layer of the white frosting on the white sponge, spreading it to the very edge. Place the lightest purple sponge on top and spread with the corresponding coloured icing. Repeat with the other sponge layers. Leaving the darkest sponge on top uncovered. Place the piping bags back in the fridge to keep firm.
To create the ombre effect, take the piping bag filled with the plain buttercream and pipe a dot of the frosting on the bottom cake layer, easing the pressure on the piping bag when the dot is the same width as the bottom white cake layer. Place a small off-set spatula in the middle of the dot, then press down and drag the frosting left for only a centimetre. Wipe your spatula. Using the lightest purple frosting, pipe another dot directly above the first dot, and then press down and drag again, before wiping the spatula. Continue all the way up the cake until you have used all five buttercreams and have an ombre column running all the way up the cake. Then repeat this process all the way around the cake, overlapping the ‘drag’ of each dot as you go. You won’t be able to drag the final column of dots, but this will be the back of the cake and you’ll find that you won’t even notice it.
Use the remaining frosting to pipe a circular ombre pattern on the top of the cake. Start with the darkest purple, and using the same dot, drag and wipe method, create a ring of icing around the edge of the cake. Make sure the ring meets the top layer of the icing on the sides of the cake. Repeat with the other frostings, finishing with just a small amount of the plain frosting at the centre. Allow the icing to set for about 10 minutes, and serve.
© Lorraine Pascale, 2017. Images: © Myles New, 2017.