Making steam banana cake

Here is it, I was baking steaming another cake yesterday, since the line is almost dead! It is pretty easy by following the ingredients here, mix well everything and within 30-40 minutes the cake is done.

I double up the ingredients to make a bigger one. The result is not that nice. The center towards the bottom of the cake is a bit hard, but still edible. Will try to follow the exact amount of ingredient next round and use different tray to steam.