Place garbanzo beans in a food processor. Pulse to desired consistancy (the more you pulse, the finer the consistancy). I like it with small pieces of beans. If it seems too dry, add a teaspoon or so of the reserved liquid. (No food processor? Mash the beans with a fork)
Place beans in a small bowl. Add rest of ingredients and stir to combine. For a creamier texture, add a little more mayonnaise.
Adjust seasoning and serve. Great on a bun with lettuce and tomato.