Take the gram flour in a bowl. Add in yogurt, soaked soya granules and 1 cup of warm water and whisk well so that there are no lumps. The mixture should be of a slightly thick consistency. Add salt and leave it covered to ferment for 3-4 hours.
Grind the green chillies and ginger into a paste. When the gram flour mixture has fermented, add the turmeric powder and green chilli- ginger paste. Adjust the seasoning and mix it well.
Heat the steamer. Grease a dhokla mould or shallow cake tin.
In a small bowl take soda bicarbonate, add 1 teaspoon of oil and lemon juice. Mix and add to the gram flour mixture and whisk briskly.
Pour batter into the greased thali and place it in the steamer. Cover with the lid and steam for 10-12 minutes.
Once it is a little cooled, cut into square shapes and keep them in a serving bowl/plate.
Heat remaining oil in a small pan. Add in mustard seeds, when the seeds begin to crackle, remove and pour it over the dhoklas.
Serve it garnished with coriander leaves and coconut.