In a small mixing bowl, combine besan (chickpea flour) and yogurt. Whisk well to make sure that there are no lumps. Set aside.
Grind onions, ginger and garlic cloves to a smooth paste.
Heat oil in a pan, add the cumin seeds and nigella seeds. Once the seeds start to splutter, add the ground onion paste and saute till it doesn't smell raw anymore and the onions turn light golden, about 6~7 minutes.
Now add the curd-besan mixture, turmeric and salt; mix well.
Bring the mixture to a boil, while stirring continuously. Add the corn kernels and mix well. Cook till the corn is heated through, about 3~4 minutes.
Serve hot, garnished with cilantro.