Combine first 4 ingredients in a large bowl; beat at medium speed with an electric mixer until light and fluffy. Add eggs, one at a time, beating until blended.
Combine flour and next 3 ingredients; add to butter mixture, stirring until blended.
Fold in nuts and chocolate.
Divide dough in half and shape each portion into a 10”x20” log on a lightly greased baking sheet.
Bake at 350 degrees for 25 minutes. Cool on baking sheet 5 minutes. Remove to wire rack to cool completely.
Cut each log diagonally into 1/2” thick slices with a serrated knife using a gentle sawing motion and place slices on ungreased baking sheets.
Bake slices at 350 degrees for 10 minutes; turn cookies over and bake 10 minutes more.
Remove cookies to racks and cool completely.