Soak gram dhall and urad dhall for 1 hour in fresh water, later strain it in a colander.
Grate the jaggery. Add the dhall in a wet grinder and just pule it a few times. Add the cardamom and jaggery and gring to a coarse paste ( do not add any water to it). Juat before transfering the contents to another bowl add semolina and plain flour and pulse it a few times for it to be mixed well. Transfer the contents to another bowl and mix in the cashews. In the mean time heat the oil in a sauce pan / kadhai. As the oil is heated lower the flame to medium heat . Make small balls out of the dhal and jaggery mixture . Just pinch and pull it you cannot make perfect roundles, It should be the size of a small lemon. Add to the hot oil and fry it until it gets a deep brown colour. It the mixture spreads in the oil it means that is extra moisture or the oil is very hot. Try adding some semolina and wait for a few minutes before frying it.