Make Batter: In a large bowl, add water, sugar, salt, hing, turmeric powder and citric acid. Whisk until sugar is dissolved.
Sift the besan into the prepared water using a strainer. Whisk it until you get a lump-free batter. Notice the yellow color of the batter.
Now beat the batter in one direction for around 5-7 minutes. Yes, you’ll get good arm exercise. After beating, you’ll notice the batter gets lighter in color and you’ll notice so many tiny bubbles in the batter.
Cover the bowl with a plate and let it rest for 10 minutes.
Add oil. Whisk again (not just mix) for a minute.
Add ginger-green chili paste. Whisk again for another 1 minute. Keep it aside.
Prep the steamer. Add around a glassful of water to the steamer, add the rack in the center, cover it with a lid and bring the water to a simmer on medium heat. Also, grease a 6-inch round or square pan (bottom and sides) with oil.
Once the water in the steamer starts simmering, add baking soda to the batter and drizzle a teaspoon of water on the soda to activate it.
Whisk the batter in one direction only until you get a super fluffy and light batter. Do not overmix.
Pour the batter into the greased pan.
Steam for 15 minutes. Check by inserting a skewer in the center it should come out clean. Remove the pan from the steamer and let it cool for 5 minutes.
Then remove it to a plate. Since I have used a springform pan, it was easy to de-mold. But if using a regular pan then loosen the sides by running a butter knife and invert it on a plate.
Cut into square pieces.
Make Tempering: Heat the oil in a pan on medium heat. Once hot add mustard seeds and let them splutter. Add sesame seeds and within seconds it starts to pop and fly around.
So immediately add curry leaves and green chilies. Fry for around 40-60 seconds. You’ll notice blisters on the green chili surface.
Add water, salt, sugar and lemon juice. Let the water come to a boil and simmer for 1 minute. Meantime, sugar will get dissolved.
Let the tempering cool down for 1-2 minutes and then pour over the khaman dhokla evenly using a large ladle or a measuring cup. Do not dump in one place. You may think it’s too much water but trust me all will get soaked up.
Garnish with cilantro and grated coconut.