To check the doneness, insert a toothpick. If the mixture does not stick, it means the dhokla is done (If the toothpick has the batter on it, then steam dhokla for another 5 minutes).
Switch off the flame and allow dhokla to cool completely.
Insert a knife around the edges to loosen up dhokla. Flip it over onto a plate and cut into slices.
For Tempering: Heat oil in a small pan, first add the mustard seeds. Let them papaya first. Now add chopped chilies and then white sesame.