Boil water in a saucepan and add in grated potatoes in that. Cook this for 3 mins and drain it. Let it sit there for 10-15 mins untill completely drained.
Now add onions, green chilli, cumin seeds, salt, baking soda in that and mix well.
Add corn flour in this and mix well.
Heat oil for deep frying.
Take a spoonful of this and press it firmly with your hands so that it forms a small dumpling like thing.
Drop the tots in the oil and fry till golden brown.
Drain in a paper towel and serve hot with ketchup.