Wash sabudana thoroughly and soak in water for 4–5 hours or overnight until soft but non-sticky.
Drain excess water completely and transfer sabudana to a mixing bowl.
Add mashed boiled potatoes and crushed roasted peanuts.
Mix in green chilies, cumin seeds, salt (sendha namak for fasting), and chopped coriander leaves.
Combine everything to form a soft dough.
Divide into small portions and shape into flat round patties (vadas).
Heat oil in a deep pan on medium flame.
Fry the vadas until golden brown and crispy from both sides.
Remove on tissue paper to absorb excess oil.
Serve hot with green chutney or sweet yogurt.