Heat oil and saute the onion and garlic over medium heat without burning.
Add all other ingredients except olive oil and raise the heat. When soup boils, lower heat to a simmer, cover and cook 20 minutes or until potato is tender.
Set aside a small scoop of the chickpeas and blend the soup until smooth. If you like, pass through a sieve as well. Add the reserved chickpeas and serve drizzled with olive oil.