In a large soup pot or dutch oven heat oil over medium heat. Stir in onion and cook, covered, stirring occasionally for 3-5 minutes. Stir in garlic, coriander and cumin and cook another minutes, stirring frequently.
Sir in broth and split peas; bring to a boil. Reduce heat and simmer, covered for one hour.
Using an immersion blender (or pour into a blender) and puree. Either pour back into pot or if using an immersion blender leave in pot and add chickpeas and tomatoes into mixture. Cook, covered until heated through (10 minutes). Garnish with cilantro.