300g Soft Light Brown Sugar
300ml Sunflower Oil
300g Plain Flour
1 tsp Bicarbonate of Soda
1 tsp Baking Powder
1 tsp Ground Cinnamon, plus extra to decorate
½ tsp Ground Ginger
½ tsp Salt
¼ tsp Vanilla Extract
300g Beauregard (Orange) Kumara , grated
100g Shelled Walnuts, chopped, plus extra, chopped and whole, to decorate
For the Cream Cheese Frosting:
600g Icing Sugar, sifted
100g Unsalted Butter, at room temperature
250g Cream Cheese, cold
Line the bottoms of 3 x 20cm cake tins with baking paper.
1. Preheat the oven to 170°C (325°F) Gas 3.
2. Put the sugar, eggs and oil in a freestanding electric mixer with a paddle attachment (or use a handheld electric whisk) and beat until all the ingredients are well incorporated (don’t worry if the mixture looks slightly split). Slowly add the flour, bicarbonate of soda, baking powder, cinnamon, ginger, salt and vanilla extract and continue to beat until well mixed.
3. Stir in the grated kumara and walnuts by hand until they are all evenly dispersed. Pour the mixture into the prepared cake tins and smooth over with a palette knife. Bake in the preheated oven for 20–25 minutes, or until golden brown and the sponge bounces back when touched. Leave the cakes to cool slightly in the tins before turning out onto a wire cooling rack to cool completely.
4. For the Cream Cheese Frosting: Beat the icing sugar and butter together in a freestanding electric mixer with a paddle attachment (or use a handheld electric whisk) on medium-slow speed until the mixture comes together and is well mixed.
5. Add the cream cheese in one go and beat until it is completely incorporated. Turn the mixer up to medium-high speed.
6. Continue beating until the frosting is light and fluffy, at least 5 minutes. Do not overbeat, as it can quickly become runny.
7. When the cakes are cold, put one on a cake stand and spread about one-quarter of the Cream Cheese Frosting over it with a palette knife. Place a second cake on top and spread another quarter of the frosting over it.
8. Top with the last cake and spread the remaining frosting over the top and sides. Finish with walnuts and a light sprinkling of cinnamon.