Grind ginger, garlic and green chillies to a smooth paste. Peel and cut potatoes into finger chips.
Heat oil and lightly fry the potato. Remove and drain well.
In the remaining oil, add peppercorns and cloves. When they crackle, add prepared paste and fry till oil separates.
Add beaten yogurt, salt and white pepper powder. Continue to cook for a minute. Add cottage cheese cubes and continue to cook till the cubes are well coated.
Add the potatoes and half of the walnut kernels. Bring to a boil. Remove from heat and garnish with the remaining walnut kernels.