Farinata (Italian Chickpea Pancake) Recipe

In a mixing bowl, combine chickpea flour and salt. Gradually add water, whisking constantly, until a smooth, thin batter forms. Let stand, covered, at least 4 and up to 8 hours. Preheat oven to 550°F (290°C) and position oven rack in second position from top. If you have a pizza stone or baking steel, set it on the rack (it will help crisp the farinata from below, but isn't required). Pour olive oil into well-seasoned large cast iron skillet and swirl to fully coat bottom in an even layer. Using a spoon, scrape any foam from surface of batter and discard. Stir batter to mix well, then pour into skillet. Stir gently to swirl oil on top of batter. Season all over with black pepper and sprinkle with rosemary leaves, if using. Turn on broiler. Set skillet on pizza stone or baking steel, or on the oven rack if not using a stone, and cook until farinata has just set, no longer jiggles, and is browned all over, about 11 minutes. Let farinata cool slightly until set. Eat warm or at room temperature.