In a large mixing bowl, combine 1 cup sooji (semolina), 1 cup dahi (yogurt), 1/2 cup water, 1 tsp grated ginger, 1 finely chopped green chili, and salt to taste. Mix well and let the batter rest for 20-30 minutes.
After the resting time, add 1/2 tsp eno fruit salt or 1/4 tsp baking soda to the batter and mix gently.
Grease a dhokla steamer plate or a deep plate with oil. Pour the batter into the greased plate and spread it evenly.
Boil 2 cups of water in a steamer or a large pot. Place the plate with the batter in the steamer and cover it with a lid. Steam the dhokla for 15-20 minutes on medium heat or until a toothpick inserted in the center comes out clean.
Once the dhokla is cooked, remove the plate from the steamer and let it cool for a few minutes. Cut the dhokla into square pieces.
For the tempering, heat 2 tbsp oil in a small pan. Add 1 tsp mustard seeds, 1 tsp cumin seeds, 1/2 tsp asafoetida (hing), and 8-10 curry leaves. Let them crackle and then pour the tempering over the dhokla pieces.
Garnish the rava dhokla with chopped coriander leaves and grated coconut. Serve with green chutney or tamarind chutney.