In a heavy-bottomed pan, dry roast sooji on a low flame for a couple of minutes. Make sure the flame is on medium-low. Cook sooji until it is light brown, stirring continuously. Once cooked, set it aside to cool.
Transfer the cooled sooji to a mixing bowl.
Add sour curd, citric acid, sugar, ginger paste, green chilies, and salt to the bowl.
Pour in water and make the batter. Add water accordingly. You may need a little less, depending on the consistency of the curd. The batter should be of thick-dropping consistency. Mix until everything is well incorporated.
Cover and let the dhokla batter rest for 15 minutes. (Read tips above)
Meanwhile, grease the bowl with oil. Greasing it properly ensures an easy slide-out of dhokla when unmolding. Set it aside.
To steam dhokla, heat water in a pan.
Once the water starts boiling, add eno.
Add lemon juice too to the sooji-curd mixture.
It will start to sizzle.
Beat it well.
The batter will become bubbly. Do not overmix the mix.
Pour batter into this greased bowl.
Steam right away. Do not let the batter sit after adding eno. Carefully place the greased bowl-with-dhokla-batter in the pan with boiling water. Cover it with a lid and steam for 20-22 minutes or until the inserted knife or toothpick comes out clean.
Remove from heat and allow it to rest for a while.
Take a greased butter knife and run it around the bowl to loosen dhokla from the sides of the pan. Carefully flip the bowl onto a plate. Light and airy dhokla is ready for tempering.
Heat oil in a pan. Add hing and mustard seeds. Once they start to crackle, add curry leaves and chilies.
Pour this tempering over the cooked dhokla. Cut into cubes and serve hot with the chutney of your choice.