firstly in a large mixing bowl take 2 ripened banana. if your having over ripened banana (black) it works great.
add in 1 or 2 tbsp sugar depending on the sweetness of banana.
mash smooth with the help of fork. but do not blend banana in mixi.
now add ¼ cup curd, 1 tsp cumin, pinch of baking soda and ½ tsp salt.
combine well with a help of spoon.
further add 2 cup maida and prepare dough.
knead for 5 minutes or till dough turns smooth.
grease the dough with a tsp of oil.
cover and rest in warm place for 8 hours.
next day, knead the dough slightly and pinch a ball sized dough.
dust with some maida and roll slightly thick than poori.
deep fry the buns in hot oil.
further fry the buns on both sides keeping flame on medium.
fry till banana poori turns dark golden brown in colour both sides.
finally, serve the banana buns / mangalore buns / banana poori with chutney or saagu. you can also have them plain.