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Dry roast a portion of the cumin and coriander. Coarsely grind the two. Heat oil in a wok or pan. Add mustard seeds, let them crackle. Add the remaining cumin and coriander seeds. After they turn golden brown, add the onions. Sauté the onions until translucent. Add the tomatoes, turmeric, chilie, hing and salt (as required). Mix well and cook tomatoes until cooked.
Remove from stove. Spread the remaining coriander, cumin powder and coarsely cracked peanuts over the cooked tomatoes. Mix in. Add the curry leaves and coriander leaves.
Great side dish for chappathis or rice dishes.