Soak the chickpeas in water overnight (minimum 6 hours), changing the water once or twice.
Rinse and drain the chickpeas and add into a large pot. Cover with water and bring to boil over medium heat. Simmer the chickpeas for 30 minutes, skimming the foam in between.
Meanwhile add tomatoes, onions, and garlic cloves into a blender.
Blend until smooth.
Add the mixture into the chickpeas pot. Keep the chickpeas simmering until done. Add salt, and cumin.
Serve hot along with lemon, cumin and chili flakes. Season up to taste.