Peel the potatoes, cut them into small pieces, and wash them 2-3 times to get rid of the starch. Soak them in enough water for 30-60 minutes.
Drain the water completely and keep it aside for 5 minutes.
Heat oil in a wide nonstick pan. When hot, add crushed garlic, udad dal, chana dal, mustard seeds, cumin seeds, and dry red chilies. Let the seeds crackle and saute till the dals starts to change color.
Add curry leaves and hing. Saute till they turn crisp.
Add chopped potatoes and cook on high flame for 2 minutes, stirring frequently.
Turn the flame to medium and spread the potato pieces in a single layer. Cook for 2-3 minutes, stir and repeat the process till potatoes get a nice crust.
Add turmeric powder and mix well.
Continue to cook till the potatoes are cooked. It will take 10-15 mins depending on the quality and pieces size of the potatoes.
Turn the flame to low and add red chili powder, coriander powder, garam masala (optional), and salt. Mix well.
Add a few curry leaves and saute the leaves till aromatic.
Crisp Potato Fry is ready. Serve hot