It's named 'ladoo' even though it isn't a sweet or shaped like one — the name stuck from its round, ball-like shape, not its flavor, which is entirely savory.
A batter of ground moong dal and urad dal is seasoned lightly and dropped by the spoonful into hot oil, frying into small, craggy golden fritters. Vendors split them open, stuff them with grated white radish, and finish with tamarind and green chutney, sold from handcarts around Delhi through the cooler months.