Cream butter in a large mixing bowl; gradually add sugar, beating well. Add melted chocolate, eggs, vanilla, and salt; mix well. Add flour to creamed mixture, stirring well. Stir in pecans and chocolate morsels.
Drop by heaping teaspoonfuls 2 inches apart onto greased cookie sheets. Bake at 350° for 10 minutes. Cool 1 minute on cookie sheets. Remove to wire racks to cool completely.
Spread bottom side of half the cookies with 1 to 2 teaspoons of Creamy Chocolate Filling. Top with remaining cookies to make a sandwich.