Peel the onions and finely dice them. Clean the spring onions and cut into fine rings. Roughly chop the cashew nuts.
Heat the butter in a pan and sauté the onion cubes and the onion rings. Add the rice and cook for half a minute. Pour the water on, add the salt and cook over high heat for one minute. Then cover and let soak for 20 minutes over a medium heat. Finally season with salt and pepper, stir in the cashew nuts and serve.