Heat olive oil in a large pot on medium heat.
Add onion and cook for 4 minutes, stirring regularly until softened.
Add garlic, garam masala, coriander and turmeric, and cook for another minute, stirring constantly.
Add crushed tomatoes, coconut milk, chickpeas and vegetable stock/broth. Bring curry to a boil, then reduce heat and simmer for 15 minutes, stirring occasionally (with pan uncovered, to allow curry to thicken slightly).
Stir in spinach, and cook until just wilted. Add salt if desired.
Serve with naan or rice, and optionally top with fresh cilantro leaves. Add some lime juice if desired for an extra kick!
