Heat the oil in a large frying pan over a medium heat. Add the sliced garlic and cook for 30 seconds, then add the onion, stir and cook until the onion turns slightly golden at the ends. Add the chilli powder, turmeric and some salt, stir and cook for another minute. Add the tomatoes and cook for 5 minutes, stirring until the tomatoes break down completely. Stir in the paste of green chilli and ginger, then the bell pepper. Cover and cook for 5 minutes, stirring frequently.

Add the spinach and cook uncovered for 5-8 minutes stirring until the spinach is wilted. Remove from the heat and serve hot, with flat breads, as a side dish or on its own.