The big secret to this cake is that it doesn’t have butter – this cake uses oil and eggs. The fresh eggs are separated, aerated and put back together in a similar way like making a baked soufflé. Before starting have all the ingredients ready, so that once beating starts, there is little time to allow the eggs to deflate while combining and getting this sponge cake into the oven.
Another big secret – It is important to have the right tin. A circular tin, with removable base, with a tube in the middle is ideal, exactly the same as what an angel food cake would be made with. If it has the metal spikes in the top, even better. The tin absolutely does not need to be greased, nor does it need to be non-stick coating. The beauty of this cake is in the rough edge. Once cooked, the cake is turned upside down, then the spikes come into action as the steam escapes from the bake, and pulls the cake away from the side.
2¼ cups plain flour, sifted
1¼ cup caster sugar
1 tablespoon baking powder
1 teaspoon fine salt
5 large egg yolks
¾ cup cold water
½ cup vegetable oil
1 teaspoon grated lemon zest
1 teaspoon vanilla extract
8 large egg whites
½ teaspoon cream of tartar
¼ cup caster sugar
50g unsalted butter
2 cups icing sugar, sifted
1 to 2 tablespoons fresh lemon juice
1 lemon, zest of
1/8 teaspoon salt
1 teaspoon vanilla extract
Lemon Curd & Mascarpone Filling
1 cup sifted icing sugar
1 cup lemon curd
Preheat oven to 160°C, fan forced 140°C. Have a clean and dry 25cm circular tube tin at the ready. Do not grease or line the tin.
Sift together the flour, sugar, baking powder and salt together into a bowl. Sift again onto a piece of baking paper.
Beat the egg yolks, water, vegetable oil, lemon zest and vanilla in another large bowl. Use electric hand mixer on high speed until smooth, for about 5 minutes. Add the dry ingredients and beat until well combined and no lumps remaining.
Beat the egg whites and cream of tartar in the bowl of an electric mixer on medium speed until foamy. Gradually add the second measure of caster sugar, beating on high speed until peaks are stiff but not dry, about 3-4 minutes.
Use a rubber spatula and fold one-quarter of the egg whites into the yolk mixture, then fold in the remaining whites. Fold until just combined, without stirring the air bubbles out.
Scrape the batter into the tube pan and spread evenly. Bake in preheated oven until the top springs back when lightly pressed and a skewer inserted into the centre comes out clean, for about 55 to 60 minutes. Remove from oven and cool upside down for at least 1 ½ hours on a wire rack.
To unmould, slide a thin knife around the cake to detach it from the outside pan, pressing the knife against the pan to avoid tearing the cake. Using the same procedure, detach the cake from the centre tube. Pull the tube upward to remove the cake from the side. Slide the knife under the cake to detach it from the bottom. Invert and allow the cake to drop onto your hand, a rack, or a serving platter. Invert again, right side up, on a rack to cool. Measure the cake, and then cut evenly into three layers. Set aside.
To make the filling: Combine the mascarpone, lemon curd, vanilla essence and icing sugar together in a bowl. Beat well until no lumps left. Spoon into a piping bag and leave chilled until ready to use. Pipe small amounts over the top of the bottom layer. Place the second layer on top and pipe remaining mixture. Do not spread with a knife, as the cake crumb will tear easily. Place top layer on the cake.
To make the icing: Melt the butter in the top of a double boiler over low heat. Remove and stir in icing sugar, lemon juice, zest and salt. Return to the heat and cook over barely simmering water for 5 minutes, stirring occasionally. Remove and add the vanilla. Beat until cool (briefly for a pourable glaze or several minutes for a spreadable icing).
Drizzle the icing over the cake. Let set and chill before serving. Serve topped with candied lemons.