In a 10-inch skillet, cook Bacon over moderate heat until crisp (about 4 minutes) and transfer to paper towels to drain. Pour off excess fat from skillet. Crumble bacon and reserve. In same skillet, melt 1 tablespoon butter over medium heat. Cook shallots in butter stirring until softened. Add dried blueberries, port and beef stock. Simmer over medium-low heat until liquid is reduced by half (about 4 minutes). Stir in balsamic, 1/4 teaspoon of salt, 1/8 teaspoon of pepper, and 1 tablespoon of remaining butter. Transfer sauce to a small bowl and stir in reserved bacon and minced tarragon. Keep sauce warm. Cook 6oz Filet Mignon to medium rare. Place each 6oz Filet Mignon on a plate and spoon over the top. Garnish with tarragon. Serves 4.