Heat the olive oil in a pot that is at least 5.5 quarts that has a lid. Once the oil is hot, add the onions and let them cook until just lightly golden brown over a medium high heat for about 4-5 minutes. Turn down the heat to medium low and let them cook another 2-3 minutes. Add the garlic and cook for 30 seconds. Quickly add the salt, cumin, coriander, turmeric and black pepper and cook another minute until the spices give off their scent. Add the tomato paste, stir so the spices are well incorporated into the tomato paste and cook for about 2 minutes, or until the tomato paste is a deep red. Add the chicken pieces and stir again until all the chicken is well coated in the tomato-onion mixture. Turn the heat up to medium and cook the chicken until it is no longer pink and is no longer completely raw. This will take about five minutes. Stir it frequently so all sides of the chicken pieces are cooking. Add the chopped tomatoes and continue to stir and cook until the tomatoes release their liquid. Add the water and then turn the heat down to medium low, cover the pan with its lid, and simmer gently for 20 minutes. 

After 20 minutes, remove the lid and add the drained and rinsed chick peas. Let the chick peas simmer and heat through for about 3 minutes. Then add the spinach. Cover the pot again and let the soup simmer for another five minutes. After five minutes remove the lid and add a squeeze of lemon to your soup and serve.