Beat butter and sugars at medium speed of an electric mixer until creamy; add vanilla and egg, beating until blended.
Combine flour, soda, and salt; add to butter mixture, mixing well. Stir in pecans and chocolate morsels. Drop dough by heaping teaspoonfuls onto greased cookie sheets. Bake at 350° for 8 to 10 minutes. Cool slightly on cookie sheets; transfer cookies to wire racks to cool completely.