Meanwhile, set the large skillet over high heat. Add the chickpeas and stir until warmed through. Add 1 cup of the sherry and boil until the pan is dry and the chickpeas begin to brown, about 5 minutes. Add the garlic and cook, stirring frequently, until fragrant, about 1 minute. Season the chickpeas with salt and pepper and stir in the remaining 1 tablespoon of sherry and 2 tablespoons of olive oil.