1. Mash the banana completely with your hands;
2. Add the rest of the ingredients, except oil, and make a dough;
3. The dough should be of the chapati dough consistency.
4. Note:
   • Be very careful while adding yogurt;
   • Yogurt gives out some water and tends to make the dough watery.
   • So, start with very little quantity and then add more, as required.
5. Cover and set aside for 4-5 hours.
6. Heat oil in a frying pan on low-medium heat;
7. A tiny ball of dough dropped into the oil should rise immediately - That's when the oil is ready.
8. Pull out ping pong sized balls of dough and pat them in between your palms to make pooris out of the dough;
9. You could also use rolling pin to make the pooris.
10. Note:
    If you are using your hands for making pooris, greasing them with a few drops of cooking oil would help.
11. Drop the pooris in oil and deep fry on both sides until they turn brown;
12. Note:
    While deep frying, press and keep them inside the oil for a few seconds, just like how you would do for ordinary pooris - This helps them fluff up!
13. Remove from oil and drain on paper towels;
14. Serve hot with coconut chutney/Sambhar and enjoy.

Courtesy: http://maneadige.blogspot.com/