Cherry is known for her ability to intergrate Asian flavours into her baking. This green tea swiss roll has made two appearances at Band of Bakers: once at the very first event in May 2012, and then again with a delicious purple sweet potato filling at the Vegetable Bakes event in January 2013. This recipe is for the latter, but simply omit the sweet potato filling and fill with cream if you prefer.
Cherry’s Green Tea Swiss Roll
For the purple sweet potato puree
3 purple sweet potatoes
4 tbsp condensed milk
2 tsp full fat milk
For the sponge
6 medium eggs, separated
100g caster sugar
50g self-raising flour
10g matcha powder
10g ground almonds
40ml full fat milk
1 tsp icing sugar, for dusting
For the filling
250ml double cream
30g icing sugar
20g caster sugar
To make the purple sweet potato puree, preheat a fan oven to 200ºc. Bake the whole purple sweet potatoes (skin on) for at least 50 minutes. Use a fork to poke the potatoes to check that they are soft enough.
One by one, cut the potatoes in half, and then use a teaspoon to scoop the flesh into a bowl. Use the back of a fork to mash the potatoes. Add the condsensed milk and full fat milk and mix well.
Use clingfilm to shape the puree into a long tube, twist to tighten both ends and keep cool in the fridge.
Meanwhile, keep the oven at 200ºc. Line a 25cm x 38cm tin with greaseproof paper. Make the sugar syrup by dissolving the sugar in the water, and bring to the boil until reduced by half. Leave it aside to cool.
Beat the yolks with 50g of the caster sugar until pale and creamy. Add half of the flour and mix well, and repeat for the remaining half. Add the ground almonds then slowly sift in the green tea powder, add the milk to loosen the mixture in between.
Use an electric whisk to beat the egg whites at a medium speed until you see lots of air bubbles. Turn the speed up to high and add the remaining 50g caster sugar a spoon at a time into the egg whites. Whisk until stiff peaks form but do not overwork.
Mix a quarter of the egg whites into the cake batter. Fod in the remaining egg whites, a quarter at a time, until fully incorporated. Pour the mixture into the prepared tin and gently spread out with a spatula. Bake in the preheated oven for 12-15 minutes.
Remove the sponge from the oven. Cool it in the tin for a few minutes then transfer to a wire rack, keeping the greaseproof paper in place. Place another piece of greaseproof paper, a little bigger than the size of the tin, on a work surface and turn the sponge upside down. Carefully remove the paper on the top. This smooth side is the outer layer of the swiss roll. Turn the sponge over so the rough side is facing up and brush on the sugar syrup, including on to the edges.
Whip the fresh cream with icing sugar until soft peaks form and then evenly spread it across the sponge. With the shorter side facing you, line the puree around 6cm – 8cm from the bottom of the sponge. Roll the sponge over the puree and carry on until it is done.
Use the greaseproof paper to wrap around the roll, twist to tighten both ends and then chill in the fridge for at least 30 minutes. Cut off both ends when ready, dust with icing sugar and serve.
More of Cherry’s recipes can be found on her blog, Feed the Tang.