Baka’s Hungarian layer cake (Torta di baka)

Instructions

1. Preheat the oven to 180°C (160°C fan-forced). Rub a bit of butter over two baking trays, then top each with a sheet of baking paper. My baking trays measured 33 cm x 28 cm.
2. To make the cake, separate the eggs, placing the yolks in the bowl of a stand mixer and the whites in a separate clean bowl. Add the sugar to the egg yolks, together with the orange juice, and beat on medium speed until thick and creamy. Add the flour, orange zest and a pinch of salt and beat for a couple of minutes until combined; the mixture will be pale and quite thick.
3. Add a pinch of salt to the egg whites and whisk (by hand, or with electric beaters) until stiff peaks form.
4. Add a heaped tablespoon of egg white to the cake batter and mix to loosen it a little. In batches, carefully fold the remaining egg white into the batter, being careful not to lose aeration.
5. Divide the mixture into two and evenly spread half the batter on one baking tray and half on the other tray, so that they almost reach the edges and are the same size.
6. Bake for 8–9 minutes, or until cooked through and golden.
7. Remove the first cake sheet from the oven and carefully invert onto a large wire cake rack. Carefully peel off the baking paper, then flip the cake back over, onto a clean sheet of baking paper. Repeat with the second cake.
8. Cut each sheet of cake in half (or into three if you would like to make a six-layer cake); my four cake pieces measured 14 cm x 24 cm. Set aside to cool completely (it won't take long).
9. To make the chocolate buttercream – dice the butter and place in the bowl of your stand mixer. Beat on medium speed for 1 minute until smooth, then add the rum, milk and vanilla. In batches (so the powder doesn't fly everywhere!), add the icing sugar and cocoa. Beat until homogenous. The buttercream will be thick but easily spreadable; if it isn't, add a bit more milk.
10. To assemble the cake – place one layer of cake on a clean sheet of baking paper, cut slightly larger than the cake.
11. Using a spatula, carefully and evenly spread about one-fifth of the buttercream over the cake. Carefully place another layer of cake on top, then spread on another one-fifth of the buttercream. Repeat until the cake is stacked with all four layers. Spread the remaining buttercream on the sides and ends of the assembled cake so that it is completely covered. Decorate the top with candied orange peel.
12. Using a thin transfer board, slide the completed cake, with the baking paper, into a sufficiently large lidded container that you can place in the fridge.
13. Refrigerate for at least 2 hours (and up to 2 days) before serving.