Put the garbanzo beans in a large bowl and fill with water to cover. Rub the beans between the palms of your hands and against each other to loosen the skins. Continue until all of the skins have been released. Discard the skins.
Transfer the skinned garbanzo beans to a food processor. Add the olive oil, tahini, lemon juice, cumin, garlic and 1/4 teaspoon salt. Process until smooth and creamy, 3 to 5 minutes. (If the hummus is not creamy enough, add more olive oil.)
To serve, spread the hummus on a round platter, sprinkle with paprika and za'atar, and drizzle with olive oil.