Heat a pan, add rava, begin to roast. Stir often while roasting the rava. Don't brown the rava. Switch off the flame and then add the roasted rava in a plate and keep aside.
Heat a kadhia, add oil and add mustard seed, when crackling sound of mustard seed, means they are getting fried. Now add cumin's, chana and urad daal, curry leaves. Immediately then add peanuts and cashews begin to fry. The cashews gets golden the dals would also get golden. Now add finely chopped onion, green chilli, ginger, saute for a minute. Then add water to this mixture. Now add salt as required.
On a medium to high flame, heat the water and let it come to a rolling boiling. When the water comes to a rolling boil, add the rava in to 5-6 batches with a spoon. Once u add the rava, stir immediately. Quickly stir and mix well. The rava grains absorb water and thus swell and get cooked.
Cover rava upma to steam for 2minutes on the low flames. Then switch off the flame, rava is cooked and upma is ready.