Spiced sweet potato cake with Muscovado frosting

What's the best way to make sure you eat your 5-a-day? Stick them in a cake! Hidden vegetable cakes are big this year so whether you're tucking bright pink beetroot into a red velvet cake, grating courgettes into a carrot cake, adding mashed potato to chocolate cake (this is apparently a thing) or opting for sweet potato like my recipe below, the results are always deliciously moist and healthy (well, sort of!). 

This is hands-down one of the most delicious cakes I've ever made. It's gently spiced, buttery, light, not too sweet and the sweet potato gives it a lovely moist texture. You could swop out the sweet potato with pumpkin or mashed butternut - I think that would be equally delish. 

The brown sugar frosting is something a little different, using Muscovado sugar, which is caramelly and rich, imparts a crazy-good molasses flavour.  

It's quite a looker this cake, and I wanted it sky-high with four layers for these photos but have adjusted the recipe below to make it three, as four is just impractical and results in HUGE slices of cake (now, depending on what kind of person you are, you may agree or disagree with this statement!). But I want to share a little secret when it comes to assembling layer cakes; freeze the cake layers. Wrap each cake in wax paper and cling wrap then freeze the night before. Make sure your frosting is at room temperature and then go about assembling your cake using the frozen layers. The cake will be rigid so it will be easy to spread (no crumbs!), the layers won't break and as you work, the frosting will set and you won't be left with a leaning tower of Pisa. Once you're done, allow the cake to return to room temperature before cutting and serving. Voila! You're welcome.

Spiced carrot and sweet potato cake with brown sugar frosting

Serves 10-12

210g butter, softened

270g Demerara sugar

3 eggs

180ml cooked and mashed sweet potato

1 tsp vanilla extract

200g self-raising flour, sifted

½ tsp bicarbonate of soda

1 tbsp cinnamon

½ tsp nutmeg

120g finely grated carrots, squeezed well

1/2 cup sultanas (optional)

75g flaked almonds

Frosting

200g butter, softened

2-3 tbsp boiling hot water

75g Muscovado sugar

300g icing sugar, sifted

250g smooth full fat cream cheese

Toasted flaked almonds, to decorate (optional)

Preheat the oven to 180C and grease and line 3 x 20cm sandwich cake tins.

Cream the butter and sugar until very light and fluffy.

Add the eggs one at a time, beating well in between each addition.

Beat in the sweet potato and vanilla.

Combine the flour, bicarbonate of soda and spices and stir into the cake batter.

Stir in the carrots, sultanas and flaked almonds then divide between the 3 tins and bake for about 40 minutes or until a skewer inserted into the middle of the cakes, comes out clean.

Allow the cakes to cool, upside down, completely then remove from the tin.

For the frosting, cream the butter until light and fluffy.

Pour the boiling water over the muscovado sugar to dissolve (pop in the microwave for a few seconds if needed) then allow to cool.

Add the cooled muscovado syrup to the butter with the icing sugar and beat until combined. Mix in the cream cheese.

Sandwich the cakes together with the frosting, leaving enough to cover the top.

Decorate with nuts, if desired.

TIP This cake batter would make fantastic cupcakes! Just fill cupcake liners 3/4 full and bake until golden. Then top with the frosting.