Peel and chop 400 gram potatoes into small pieces. Make sure that potatoes are cut into uniform pieces.
Put all the chopped potatoes into boiling water.
In the meantime take a bowl and put a sieve over the bowl. Also keep a fork, spoon and spatula handy.
Boil potatoes for 8-10 minutes or until they are cooked yet firmed. You can check it by inserting a fork.
Strain the potatoes and transfer them into sieve/strainer.
While they are hot, immediately start mashing the potatoes using a fork.
Once they are completely mashed, press them using the back side of the spoon in such a way that a fine mash passes through the strainer.
Also keep on scraping the base of the strainer using spatula.
All the fine mash is collected in the bowl.
Add 1 cup of corn flour/corn starch.
Mix very well.
Now start adding water, but very little at a moment, and keep on kneading a dough. Be careful while adding water.
Knead the potatoes into a crack free dough.
Take a small piece of dough from the entire dough.
Roll this small piece of dough into a crack free smooth ball having no cracks.
Take a glass bottle and dip it's mouth into oil.
Place the mouth of bottle over the ball and gentle press the bottle.
You will get the shape of potato ball like a mushroom.
Likewise prepare all the balls. We could make 21 balls out of the entire dough.
Transfer these 21 potato starters into boiling water contained in a large pot.
In 3 to 4 minutes, these mushroom looking starters will begin to float on the top of water.
Immediately transfer them from boiling water to ice cold water.
Let them sit there for 5 minutes or until completely cool.
Take them out of the cold water and put in a separate bowl.