- 170 g sultanas optional
- 3 tbsp dark rum optional
- 340 g walnuts chopped
- 450 g carrots peeled, coarsely grated
- 340 g buttermilk
- 2 tsp cinnamon ground
- 2 tsp ginger ground
- ½ tsp nutmeg freshly grated
- 2 tsp baking powder
- 1 tsp salt
- 4 eggs large
- 50 g sugar granulated
- 250 g sugar dark brown
- 2 tsp vanilla extract
- 85 g vegetable oil
- 50 g butter softened
- 200 g cream cheese full-fat
- 100 g icing sugar
- 1 orange Finely grated zest
Preheat oven to Gas Mark 4. Lightly coat two 9"-diameter cake pans with vegetable spray. Line bottoms with parchment paper rounds; lightly coat rounds with nonstick spray. If using raisins and rum, heat together in a small saucepan over low just until warm, about 2 minutes. Remove from heat and let sit until liquid is absorbed and raisins are plump, 15–20 minutes.
Meanwhile, toast walnuts on a rimmed baking sheet, tossing once, until golden brown, 8–10 minutes; let cool.
Combine carrots and buttermilk in a medium bowl.
Whisk flour, cinnamon, ginger, nutmeg, baking powder, salt, and baking soda in a large bowl. Using an electric mixer on high speed, beat eggs, granulated sugar, brown sugar, and vanilla extract until pale and thick, about 4 minutes. Reduce speed to medium-low and gradually stream in oil. Add dry ingredients in 3 additions, alternating with carrot mixture in 2 additions, beginning and ending with dry ingredients; mix until smooth. Fold in raisins, if using, and walnuts with a rubber spatula. Scrape batter into prepared pans.
Bake cakes, rotating pans halfway through, until a tester inserted into the centre comes out clean, 35–45 minutes. Transfer pans to a wire rack and let cakes cool 10 minutes. Run a knife around sides of cakes and invert onto wire rack; remove parchment. Let cool completely.
For the icing, beat the butter in a large bowl with a hand mixer until really soft. Add the cream cheese and beat again until well mixed. Sift over the icing sugar, add the orange zest, then beat until smooth. Store, covered, in the fridge until needed.
For the orange peel, carefully pare the zest from the orange (a tool like this would be helpful). Put the water and sugar in a saucepan and heat until the sugar has dissolved. Add the orange zest and remove from the heat. Let the zest sit in the sugar syrup until it has completely cooled.
Spread half the icing between the cake layers and the other half on top. Decorate with the orange zest strips.
There is no way we'd call this 'healthy' it is though delicious and makes for an alternative festive desert