I consider myself lucky to have experienced authentic Gujarati cuisine when I was in the hostel studying for my post graduate degree in Mumbai. People not familiar with Gujarati cuisine use the term khaman dhokla without realizing that there is no such dish. There is dhokla which is made using rice flour and khaman is made using chick pea flour or besan.

My mother used to make khaman by using a few tablespoons of idli batter as leavening agent. I used the same technique. Also I used a sponge cake tin (20 centimeter diameter) as a vessel for the batter and steamed in my Dutch oven.
INGREDIENTS
1 and a ½ cups of chick pea flour or besan
4 tablespoons idli batter
5 centimetre piece of ginger
3-4 green chillies