On a separate pan, sauté the onion in the olive oil until it becomes translucent. Add mushrooms and Marsala wine. Cook for about 3 minutes and add kale, salt and some pepper. Cook until kale reduces its size and looks fully steamed. Turn heat off. Add the cooked black rice mixing it well. Taste and adjust with more salt and/or pepper. Cover and let it stand for a few minutes, allowing the rice to absorb the kale/mushrooms/Marsala wine juice. Sprinkle the cheese over the rice before serving.