Mix all the above ingredients and make small lemon sized balls, roll them in corn flour and deep fry in vegetable oil until golden brown.
Heat butter with 1tbsp of olive oil in a cooking vessel and add the cumin seeds and let them pop. Add the onion paste and fry for 4-5 minutes on medium heat ensuring that it doesnt burn. Add the ginger garlic paste and fry for another 2-3 mts. Add chili powder,turmeric powder,coriander powder combine. Add the tomato puree and let it cook over slow fire till the oil separates. Now add the spinach paste and cashewnut paste . Add a cup of water and salt. Cover and cook for 10-12 minutes on low heat. Stir once in a while. Lastly add the garam masala and mix well. Turn off heat.
Just before serving, spread the koftas on a serving plate and pour the creamy gravy over the koftas and garnish with cream (optional). Serve with hot rotis or naan. If you are serving the dish immediately on cooking, then you can add the koftas to the gravy and simmer over heat for a minute before serving.