Dry roast oats for 10-15 mins on a low flame and grind them into a coarse powder,keep it aside.
Dry roast semolina for 10 mins on low flame,keep it aside.
Mix all ingredients into a smooth batter except eno fruit salt.
Grease a vessel with oil.
Add eno fruit salt to batter and mix well.Pour the batter into the greased bowl.
Steam for 15-20 mins or until cooked.
Allow it to cook, cut into pieces.
For tempering:
In an pan, heat oil.
Add mustard seeds,curry leaves and chillies.
Spread this mixture on the steamed dhokla.
Serve hot with chutney.
Notes
You may also start with pre-grinded oats powder.Just roast that with semolina.Also, you will need to add 1-2 tablespoon additional water in case of oats powder.