1. Cook the onion, ginger and hot pepper in the oil over medium-high heat until they start to brown. Add the garlic and cook another 45 seconds.
2. Add the mushrooms and stir well. When the mushrooms have started browning, add the spinach, the spices, and the salt.
3. Add the water, reduce the heat to medium-low, cover and cook for 10 minutes. Uncover and continue to cook until all the liquid has evaporated.
4. Off the heat, add the yogurt and stir well to combine. Adjust seasonings and serve at once.