Sweet Potato Chiffon Cake

Had a gathering today and the theme was purple. Each of us had to make/buy an edible purple item. The first thing that crossed my mind was purple sweet potato because my maid cooked some sweet soup with this last week and the sweet soup was nicely purpled. Having set my mind on that purple sweet potato, I decided to stick to what I do best - chiffon cake.

After mixing and blending in the egg white, I know that my cake will not be very purple in color. The batter sort of became Mauve in color. The original purple color of the sweet potato is very intense, just like those cubes you see embedded in the cake.

Anyway, the color of the baked cake is very pretty. The cake has very subtle sweet potato taste, without those cubes of sweet potato embedded, one wouldn't even guess that it was a sweet potato chiffon cake.

I have fun doing chiffon cakes with natural ingredient that gives you natural colors. Let's think what other natural colors we can give to chiffon cakes.



Ingredients: (17cm chiffon tube pan)

100g purple sweet potato (steam and mashed)
3 tbsp milk

(A)
3 egg yolks
20g brown sugar
pinch of salt
50ml corn oil
3 tbsp water

(B)
85g cake flour

(C)
4 egg whites
50g sugar
1/2 tsp cream of tartar

(D)
Diced steamed sweet potato cubes (optional)

Method:
1. Steam sweet potato, add milk to it and mashed till fine or blend it in a blender.
2. Mix all ingredients in (A) till well blended. Add in (1) and mix well. Sieve in (B) and mixed till smooth and lump-free. If batter is on the dry side, add a tablespoonful of water - some purple sweet potatoes can be quite dry.
3. Beat egg whites in (C) till stiff.
4. Add half portion of egg white mixture into egg yolk mixture and mix well with a spatula.
5. Pour egg yolk mixture into the remaining white and mix till well-combined. Stir in (D) - sweet potato cubes.
6. Pour batter into chiffon pan. Bang the cake pan a couple of times to release air bubbles in the batter.
7. Bake at 180C for 30 minutes or till cooked.