Combine 2 cups chickpea (garbanzo) flour, 2 cups warm water, 2 Tbsp. olive oil, and 2 tsp. salt. Let rest 2 or more hours. Meanwhile, thinly slice 1 small zucchini and 1 red onion. Sauté briefly in olive oil until lightly browned, then set aside. When ready to cook, turn on broiler. Oil an oven-safe skillet or jelly roll pan and heat in the oven 3 minutes. Remove pan and pour in about 1½ cups batter, until it's about ¼ thick. Top with some of the zucchini and onion, a sprinkling of chopped fresh rosemary, and a few pine nuts (optional). Place socca under broiler until edges are brown, batter is set, and toppings are beginning to crisp, 10 to 12 minutes. Slide out of pan and cut into slices. Repeat with remaining batter and toppings.
—Rachel Mount, O assistant editor