Raspberry ripple frozen yogurt with sponge drops

Method

1. Place the yogurt, sugar and lemon zest in a bowl and stir to dissolve the sugar. If you have time, cover and chill for 1-2 hours to allow the flavours to develop. Pour into a loaf tin lined with cling film or a rigid, plastic freezerproof container and freeze for about 1 hour.
2. Meanwhile, place the raspberries in a food processor with the icing sugar and lemon juice. Blitz until smooth. You can sieve the raspberry sauce at this stage to remove the seeds if you like.
3. After 1 hour, remove the yogurt from the freezer. It should be semi-frozen; using a skewer, swirl through the raspberry sauce. Return to the freezer for a further 3 hours.
4. To make the sponge drops, preheat the oven to 180°C/fan160°C/gas 4 and grease 2 x 12-hole shallow bun tin (the type you’d use for mince pies) with the softened butter. Place the eggs, sugar and vanilla extract in a bowl and beat with an electric hand whisk until thick and doubled in volume. Carefully fold in the flour and baking powder, divide between the bun tin holes until filled and bake for 10 minutes, until puffed up and pale golden. Leave to cool for a few minutes, then remove from the tin and cool completely on a wire rack.
5. Remove the frozen yogurt from the freezer and allow to soften. Split the sponge drops and fill with a scoop of the frozen yogurt. Dust with icing sugar and decorate with extra raspberries, if you like.