In large mixer bowl, cream butter, sugar and salt. Beat in vanilla. Gradually beat in flour; stir in morsels and pecans. Shape level tablespoonfuls of dough into 1 inch balls. Place on ungreased baking sheets. Bake in preheated 375°F. oven for 10 to 12 minutes or until cookies are set and lightly browned. Remove from oven. Sift powdered sugar over hot cookies on baking sheet. Let stand for 10 minutes. Remove to wire racks to cool completely. Sprinkle with additional powdered sugar if desired. Store in airtight container. Makes 5 dozen cookies.