Bolu kukus is an Indonesian traditional steamed cupcake. I personally am not really fond of them. I preferred lemper rather than bolu kukus, but now I am curious. The term 'mekrok' is literally blooming. In this case, the surface of the cupcakes when successfully steamed will be cracked wide open, like someone is laughing from ear to ear. I have tried many times, with very little knowledge about how to, and failed many times, too. Like these cupcakes:
The surface of the cupcakes are not quite cracked and wide open. It's just like someone is timidly smiling at you.
I have made notes out of failures. One of them is the requirement of deep steamer. I need it for this work, as when the cupcakes are rising, they tend to touch the lid. That, perhaps, causes the cupcakes stay 'frowning'. But, then one of NCC members gave a suggestion to use anything that can hold the cupcakes while steamed, while still get a lot of steam from inside the steamer. I thought hm, ramekins can do that, but they will be too high if you put them upside down, so I just place the cupcakes inside the ramekins. This is just like bain marie. And, it works!
Looking at them, I came to a thought: why don't they have that neat crack like these ones displayed here? Beats me. I don't really know what happen to them. Perhaps they just want to laugh out loud.
The recipe can be found at Hesti's or Prehati's. And this is the recipe I translated in English, in case you want to make it, too.
2 buah telur (2 eggs)
1 sdt emulsifier (1 tsp emulsifier)<-- I NEVER use it
250 gr gula kastor (caster sugar)
250 gr terigu kunci biru (plain flour) <-- I use gluten-free mix, same amount
50 gr maizena (cornflour)
80 gr DCC dilelehkan (dark chocolate, melted)
200 cc santan instan (coconut milk) <--- I use sparkling grape juice
Pasta coklat secukupnya (chocolate paste) <--- I NEVER use it
Preheat the steamer (simmer). Line the cupcakes tin with paper. Beat eggs, sugar and emulsifier until thick. Add in wet ingredients a little at a time, fold in flour, chocolate, and wet ingredients (including melted dark chocolate) while the machine running in high speed. All this beating takes 15 minutes from the beginning till finished. Pour the batter in the tin about 7/8 full. Steam for 20 minutes.