Start by heating the fat and cooking the onion until it is translucent. Then put in the garlic and the mushrooms and sauté these until they begin to soften. After that, add the tomatoes, ginger, chili powder, cardamoms and garam masala, the cilantro/coriander leaves and salt. Stir these in well. Finally, pour in the water or juice and cook gently for 5-10 minutes until the mushrooms are very soft. Serve with rice or chapatis.