When you first add the spinach in with everything, it will look like there are way too many chickpeas. As you continue to mix the spinach and it looses some excess water, it will spread around the chickpeas and magically your ratio of spinach to chickpeas will seem to even out. If you are worried that the dish is drying out, add a little more olive oil.
Cooking time does not account for cooking of the chickpeas, so make sure you take that into consideration. Many people make this recipe with canned chickpeas and frozen spinach, but we prefer to use fresh products. A pressure cooker can also be used to cook the chickpeas if you want to save on time.
Although it's not traditional, and the dish is still excellent without it, we like to give a squeeze of lemon over our espinacas con garbanzos once in a while to brighten it up a bit.