Preparation Line baking sheet with foil. Using large sharp knife, quarter pineapple lengthwise through leafy top. Core each wedge. Cut pineapple flesh from peel of each wedge, keeping flesh in 1 piece. Set aside. Transfer pineapple shells to baking sheet. Cover leaves with foil to protect from heat. Preheat broiler. Melt butter in heavy large skillet over medium heat. Add sugar, water and cinnamon. Bring to boil, stirring until sugar dissolves. Remove from heat. Add rum to sauce; ignite with match. (Pineapple and sauce can be prepared 1 day ahead. Cover pineapple and sauce separately. Bring sauce to simmer before continuing.) Add pineapple wedges to skillet. Cook until heated through, turning to coat, about 4 minutes. Return pineapple to shells. Boil sauce until thick, about 2 minutes. Cut each pineapple wedge crosswise into 1/2-inch-thick slices, keeping shells intact. Spoon sauce over pineapple. Broil until sauce bubbles and browns slightly, about 3 minutes. Transfer to plates.
Preparation Line baking sheet with foil. Using large sharp knife, quarter pineapple lengthwise through leafy top. Core each wedge. Cut pineapple flesh from peel of each wedge, keeping flesh in 1 piece. Set aside. Transfer pineapple shells to baking sheet. Cover leaves with foil to protect from heat. Preheat broiler. Melt butter in heavy large skillet over medium heat. Add sugar, water and cinnamon. Bring to boil, stirring until sugar dissolves. Remove from heat. Add rum to sauce; ignite with match. (Pineapple and sauce can be prepared 1 day ahead. Cover pineapple and sauce separately. Bring sauce to simmer before continuing.) Add pineapple wedges to skillet. Cook until heated through, turning to coat, about 4 minutes. Return pineapple to shells. Boil sauce until thick, about 2 minutes. Cut each pineapple wedge crosswise into 1/2-inch-thick slices, keeping shells intact. Spoon sauce over pineapple. Broil until sauce bubbles and browns slightly, about 3 minutes. Transfer to plates.