Sweet potato cake with orange mascarpone frosting

Like pumpkin, sweet potato gives a lovely softness to a cake’s texture, as well as a warm glow. Its sweetness means you can scale back the sugar, too.

SERVES 16 INGREDIENTS

500g sweet potatoes 120g butter

110g caster sugar

2 eggs, at room temperature ½ tsp cinnamon

110g self-raising flour 110g spelt flour

2 tsp baking powder

1 tsp bicarbonate of soda 90ml milk

For the frosting

50g raspberries 250g mascarpone Zest of ½ orange

2-3 tbsp milk (if required)

METHOD

Turn on the oven to 200C/180C fan/Gas 6 (there’s no need to preheat it).

Put the potatoes on a baking sheet and bake for 45 minutes or until tender all the way through, then leave to cool.

When cool enough to handle, peel off the skin and purée the flesh in a food processor. Weigh out 225g: the rest can be added to soups or stews.

Turn the oven down to 180C/160C fan/Gas 4 and line a 20cm square cake tin with baking parchment.

Cream the butter and sugar together until pale and fluffy. Beat in the eggs one at a time, then beat in the cinnamon and potato purée.

Mix together the flours, baking powder and bicarbonate of soda, and sift this over the egg mixture, folding it in. Gently stir in the milk.

Scrape the mixture into the tin and bake for 40 minutes, until a skewer pushed into the centre comes out clean. Leave to cool in the tin, then remove to a wire rack.

Rub the raspberries through a sieve to make a purée. Beat the mascarpone with the orange zest. If it needs it, add a little milk for a spreadable consistency. Spread this over the cake and marble in the raspberry purée.