Oil an 8-inch diameter flat container. I used a cake pan.
Next, get your steamer ready. If you don’t have a steamer, just take a large vessel like a big saucepan or a big wok that can fit your 8-inch container and the vessel should have a tight lid too. To convert that vessel into a steamer, you need to find something circular that you can be placed at the base of the vessel and on top of that, you have to place the 8-inch container. Remember that whatever you place at the base of the vessel must allow the steam to come up. So, a definite no to plate! Look for a big strainer or tart pan ring.
Pour 1½ cups of water in the vessel and bring it to a boil.
In the mean time, get the batter ready. Add chickpea flour, turmeric, sugar and eno salt in your stand mixer bowl. Give it a quick whisk. Then, pour, 1½ cup of water and oil. Whisk it at a high speed for a couple of minutes. The batter should come together very quickly and it would look quite foamy.
Pour the batter immediately to the oiled container or cake pan. Then, place it on the large vessel.
Cover the large vessel with a tight lid making sure no steam escapes while cooking.
Cook at medium heat for about 15 to 20 minutes.
While the khaman dhokla gets cooked, prepare the tampering.
Heat 1 tablespoon of oil in a tiny saucepan and scatter mustard seeds along with asafoetida, curry leaves, chopped green chili and a couple of whole green chilies. Allow it to cook for two minutes. Then, pour water along with sugar, give it a stir and allow it to boil for a few minutes. Once done, switch off the heat and allow it cool off a bit.
Finally, check the dhokla by inserting a knife or a toothpick in the center. If it comes out clean, the dhokla is ready. Take it off the steamer and loosen the side by running a knife along it. Flip the dhokla on a serving plate and pour the warm syrup on top.
Slice into bite size portions and serve.