Preparation Whisk together flour, brown sugar, baking powder, and salt in a large bowl, then add water and egg and whisk until batter is smooth. Peel plantains and cut on a slight diagonal into 1/2-inch pieces. Stir into batter to coat well. Stir together granulated sugar and cinnamon in a shallow bowl. Heat 1/2 inch oil in a 10-inch heavy skillet over moderate heat until thermometer registers 340°F. (See cooks' note, below.) Fry plantain slices in batches of 6 (don't crowd them) until bottoms are golden, about 45 seconds, then turn over and fry until other side of each is golden, 30 to 45 seconds more. Transfer with a slotted spoon to paper towels to drain. While still warm, toss each batch in sugar mixture until coated, then transfer to a platter. Serve hot or warm. Cooks' note:To take the temperature of a shallow amount of oil with a metal flat-framed deep-fat thermometer, put bulb of thermometer in skillet and turn thermometer facedown, resting other end (not plastic handle) against rim of skillet. Check temperature frequently.
Preparation Whisk together flour, brown sugar, baking powder, and salt in a large bowl, then add water and egg and whisk until batter is smooth. Peel plantains and cut on a slight diagonal into 1/2-inch pieces. Stir into batter to coat well. Stir together granulated sugar and cinnamon in a shallow bowl. Heat 1/2 inch oil in a 10-inch heavy skillet over moderate heat until thermometer registers 340°F. (See cooks' note, below.) Fry plantain slices in batches of 6 (don't crowd them) until bottoms are golden, about 45 seconds, then turn over and fry until other side of each is golden, 30 to 45 seconds more. Transfer with a slotted spoon to paper towels to drain. While still warm, toss each batch in sugar mixture until coated, then transfer to a platter. Serve hot or warm. Cooks' note:To take the temperature of a shallow amount of oil with a metal flat-framed deep-fat thermometer, put bulb of thermometer in skillet and turn thermometer facedown, resting other end (not plastic handle) against rim of skillet. Check temperature frequently.