Mash garbanzo beans in a large bowl. Add all remaining ingredients except olive oil. Use your hands to mix thoroughly.
Using a 1/2-cup measure, scoop mixture into balls, then flatten to form patties.
Heat 1 teaspoon oil in a cast-iron or nonstick skillet over medium-high heat. Add patties and cook in batches, 3 to 4 minutes on each side, until lightly brown. Lower heat if burgers start to brown too quickly. Serve on buns with toppings of your choice.