The chiffon cake turned out beautifully with a natural pastel purple in colour. The cake was soft and cottony and had a subtle taste of sweet potato with every bite.
ingredients ( 20 cm / 8 inch Chiffon )
Egg Yolk Mixture
- 4 Egg Yolk
- 20 g Caster Sugar
- 1/8 tsp Sea Salt
- 90 g Fresh Milk
- 45 g Cake Flour
- 40 g Japanese Rice Flour
- 100 g Purple Sweet Potato
- 50 g Vegetable Oil ( Add with milk , Optional )
- 5 Egg White
- 1 tsp Lemon Juice
- 35 g Caster Sugar
1. Wrap sweet potatoes with aluminium foil and baked in oven at 220ºC for 30 ~ 40 minutes. You may also cook the purple sweet potato in the in a steamer for 20 minutes until soft. But i recommend baking.Peel, and crumble 140 g of the potato into a bowl.
2. In a mixing bowl. Beat egg yolk with caster sugar, sea salt, beat egg yolks until light and fluffy using a electric mixer. Add little by little mashed sweet potatoes follow by milk. Mix well. Sift in plain flour and rice flour, mix well.
3. Preheat oven to 170°C
4. Make meringue – Combine sugar and cream of tartar. Beat egg whites until foamy. Add lemon juice and beat peaks curl over. Add sugar in 3 separate rounds beat until egg whites are glossy, with stiff peaks.
5. Fold 1/2 of egg whites into the yolk mixture and fold gently until combined with a rubber spatula. How to fold egg white Video Click Here
6. Then pour in the fold egg yolk back to the meringue and fold gently until combined with a rubber spatula.
7. Pour the batter into the prepared cake pan. Gently bang the pan on the table top to release air bubbles.
8. Bake at lower rack in the oven for about 40 minutes. I reduce heat to 160°C for 30 minutes but still get burn. Try to err to the side of caution if you are making it the first time.
9. Test with a toothpick, if nothing stick on it, it is done. Invert cakeon a wine bottle and cool completely in the pan. Run a thin-bladed knife around the inside of the pan and the center core to remove the cake. Release the cake and run the knife/spatula along the base of the pan to remove the cake.
- Cover the cake 5 ~ 10 minutes inside oven before finished baking to prevent cake burn or crack.