Add in the crushed tomatoes and vegetable stock and stir until mixed. Then once it starts to boil, reduce heat down to medium. Let the stew simmer for 25 minutes, stirring often. Add in chickpeas, mushrooms and currants and let simmer until the mushrooms soften. After about 10 minutes, let cool and serve in bowls, topped with yogurt, crushed nuts and cilantro. Enjoy!