1. First crush the cumin seeds, garlic in a mortar pestle.
2. Cut the sweet potato in small pieces and boil them.
3. Take some oil in a pan add mustard seeds, whole red chilli, urad dal, chopped onion, turmeric powder, curry leaves, green chilli, salt to taste.
4. In this add crushed garlic, cumin seeds paste, and sauté it.
5. Add chilli powder, sweet potato and sauté it, let it fry for 3 minutes.
6. Serve this hot with chapatti, naan or rice.