Whisk chickpea flour and water together in a bowl until smooth; let sit at room temperature, about 2 hours.
Preheat oven to 450°F. Coat an 8-inch metal pie pan with cooking spray. Skim foam from the top of chickpea-water mixture. Add oil, Italian seasoning, and rosemary and stir until combined. Pour mixture into prepared pan; sprinkle pepper and salt over top. Bake until edges begin to brown, about 15 minutes. Remove bread from pan and cut into wedges. Makes 8 servings.
Approximate Nutrient Analysis per slice (not including salt to taste):
80 calories, 4.5 g fat, 0 g saturated fat, 0 mg cholesterol, 10 mg sodium, 7 g carbohydrate, 1 g fiber, 1 g sugar, 3 g protein