snow white swiss roll cake 雪白蛋糕卷

i want to use up all my egg whites…
i want a soft and healthy cake
when you are a baker, you can do anything you want.. after all, only you will know what happen in the kitchen
我要将蛋白用光光。。
我要一个松软又健康滴蛋糕。。
当你懂得烘焙时，只要是自己要滴，都可满足。。毕竟，厨房里发生啥事儿，只有 you 和 you 知道
(´▽`ʃƪ)

Ingredients 

200g cold egg white (c. 5 large egg white)
50g sugar (A)
8g cornstarch

50g soy milk (sweetened or unsweetened is fine)
20g coconut oil
30g sugar (B)
58g cake flour
2-3 drops vanilla extract

filling
245g sweet potato (net weight after steaming & de-skinning)
4 – 4.5 tbsp sweetened soy milk
* feel free to add some sugar if you like sweet filling. but the natural sweetness from sweet potato and soy milk is enough for us

食材

冷蛋白 200克 （约 5大颗蛋白）
糖 50克 （A）
粟粉 8克

豆浆 50克 （甜或无糖豆浆允可）
椰子油 20克
糖 30克 （B）
蛋糕粉 58克
香草精 2-3滴

内陷
紫薯 245克（蒸熟并去皮后的净重）
甜豆浆 4 – 4.5大匙
＊如爱甜食，可随意在搅拌紫薯时加入些糖。但紫薯和豆浆的微甜对我们来说已足够

Directions/做法

– Mix coconut oil and sugar (B) together, then stir in soy milk. sift in flour and fold well
椰子油和糖 (B) 拌匀，加入豆浆。筛入面粉、翻拌均匀

– line a 25 x 25cm baking sheet with baking paper
25 x 25厘米烤盘铺上烘焙纸

– beat egg white with cornstarch till frothy. then add in sugar (A) in 2 additions and beat till stiff peak. change to low speed and beat for 1-2 mins to stabilise meringue texture
蛋白加入粟粉，打至出泡。糖 (A) 分两次加入，打至硬性状态。电动打蛋器转至低速继续打1-2分钟以去气泡，稳定蛋白霜

– add 1/3 meringue into the above and mix lightly. then add in another 1/3 of meringue and fold well
以上面糊加入三分之一蛋白霜，拌匀后，再加入三分之一蛋白霜。翻拌均匀

– pour the above into the remaining meringue and stir well. add a few drops of vanilla extract and stir quickly
将以上面糊一口气倒入剩余的蛋白霜，拌匀。加入几滴香草精，再次翻拌均匀

– pour batter onto pan, even out well and bake for 18 mins in preheated oven of 160 degrees C
将面糊倒入烤盘，刮平，送入预热至160摄氏度烤箱烤 18分钟即可

– remove from oven, and cool cake with the bottom of cake facing up (i.e. the pale side)
从烤箱取出后，蛋糕底部朝上（白色那面），进行完全冷却

– cut sweet potato into small pieces, and add 4 – 4.5tbsp of soy milk in food processor. blend well. the consistency of the puree should be like nutella
紫薯切小块儿后和豆浆放入食物搅拌器搅拌均匀。拌匀后的紫薯泥应该和 Nutella 巧克力榛果酱一样浓度

– spread sweet potato puree on cake and roll up tightly. chill for a few hours before slicing and serving
蛋糕体抹上紫薯泥后卷紧。冷藏数小时后即可切片享用

i am submitting this post to Best Recipes for Everyone: BREE #10 Secret of Chiffon & Roll Cakes organised and hosted by Fion of XuanHom’s Mom