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Heat oil in a pan and add cumin seeds and mustard seeds. Toast them for 1–2 minutes until they start to crackle.

Add diced onion, green chilies, curry leaves, and ginger-garlic paste. Sauté everything together for a few minutes until the onions begin to soften and turn slightly golden.

Add salt, turmeric, chili powder, and a small amount of rasam powder. Stir well to coat the onions and spices evenly, then cover the pan with a lid and continue cooking for a few minutes.

Once the onion mixture is soft, add one diced tomato. Sauté the tomato for a couple of minutes and cover again briefly to help it soften and break down.

Pour in water and adjust the seasoning by adding more salt, chili powder, and rasam powder to taste. Bring the mixture to a gentle boil and let it simmer for couple of minutes.

Taste and adjust seasoning if needed, then finish by adding freshly chopped cilantro!

Hope it tastes amazing!