In large saucepan, cook 1 cup wine over medium-high heat until it reduces to 3 tablespoons, about 10 minutes, stirring occasionally. Reduce heat to medium-low, and add butter, brown sugar, cocoa powder and salt, stirring occasionally until completely liquid and very warm to the touch. Remove saucepan from heat. Quickly add eggs and vanilla and whisk until combined. Add larger portion of candy and stir until completely melted. Add flour and stir until batter is very shiny and combined. Pour into prepared pan. Bake 24-26 minutes, or until toothpick inserted in center of pan comes out clean.