Purple Sweet Potatoes Chiffon

Method:
Preheat oven at 160C

1. Boil or steam the purple sweet potato with skin till soft. Leave to cool slightly and remove the skin. Mash (90g) and dice (120g) accordingly. Set aside.

2. Sieve cake flour, set aside. Sieve corn flour, set aside.

3. Put egg yolks, water, mashed sweet potatoes and oil in a mixing bowl, used a handheld electric mixer to mix till incorporated. Add in lemon juice (Note: the mixture will turn into light pink), follow by sifted cake flour and mix well till thick & smooth. Set aside.

4. In a clean & dry mixing bowl, whisk egg whites until foamy, gradually add in sugar and finally add in corn flour. Continue whisk till soft peak form, smooth and shiny. Do not over beat the whites still stiff, it is better to beat the whites still soft peaks for easy folding with the yolk batter.

5. With a spatular, gently fold in 1/3 of the egg whites mixture into the egg yolks mixture. When everything well combine then gently fold in remaining egg whites mixture till smooth flowing.

6. Fold in sweet potato chunks till combine.

7. Pour batter into a 20cm tube pan. Tap the pan lightly on a table top to get rid of any trapped air bubbles in the batter. Bake in preheated oven for 50 mins.

8. When baked, turn upside down to cool. Unmould when completely cool.