Combine dried cherries, port, brown sugar, and allspice in a medium microwaveable bowl. Cover and cook for 2 minutes. Let cool and pulse mixture in a small food processor or blender into a coarse chop. Preheat oven to 400 degrees and line a baking sheet with parchment paper. Cut puff pastry into 24, 1 1/2” squares, reserving scraps for another use. Cut a smaller square inside each piece and prick inside the small square with a fork. Place puff pastry squares on prepared baking sheet. Brush with egg white and sprinkle with sugar. Bake for 9-10 minutes or until puffed and golden brown. Press down centers to make a small square indent. While still warm, scoop a heaping 1/2 tsp Brie into each indent and top with port-infused cherries. Garnish with confectioners sugar and serve.