Traditional Steamed Sponge Cake

My Sundays are filled with domestic chores and time alone with my cat. The quality time spent with my cat are mostly of passive aggressive cat behaviour, which includes him evading from my pets and hugs, and him attempting to trip me by rubbing his neck all over my leg when I am trying to walk. Water supply is still rather erratic in my part of the city, which makes cooking difficult - I've been thawing and re-freezing the same raw chicken breast, giving up as soon as the kitchen tap refused to run.

Browsing through blogs, I thought of making something simple and fun, so I am choosing Sonia's 鸡蛋糕recipe, which consisted only 3 ingredients measured by bowls. Easy peasy. Added a touch of red dots for a touch of cheerful colour. I am curious though, is it normal for this steamed cake to be not perfectly domed, or did I make a mistake somewhere?

Ah Mah’s Traditional Steamed Sponge Cake 鸡蛋糕
(recipe source: adapted from Nasi Lemak Lover)
Ingredients
One bowl all purpose flour (140g)
One bowl egg (5 medium eggs)
One bowl sugar (240g)

Direction
1. Dry flour under hot sun for an hour (baked in the oven in the lowest heat for an hour).
2. Beat egg and sugar in a mixer over low speed for 2 minutes, increase to medium high speed and continue beat till double in volume (takes about 30 minutes), thick, creamy and passed “ribbon” stage. Change to low speed, beat for 1-2 minutes as to minimize the air bubbles.
3. Sift in flour, mix slowly with a spatula and combine well.
4. Pour the cake mixture into prepared 8” lined baking tin or bamboo steam tray, rest for 10mins.
5. Steam over high heat for about 15 minutes, and wait for 1 minute then only remove the cake.
6. Serve after slightly cool down.

I am submitting this post to Aspiring Bakers #25 - Steaming Hot Cakes (November 2012) hosted by Miss B of Everybody Eats Well in Flanders.