Preheat oven to 375°F. Spray a large cookie sheet with non-stick cooking spray.
Combine oats, flour, brown sugar, baking soda, cinnamon and salt in a large bowl; set aside. Beat butter, corn syrup, egg and vanilla in a small bowl until thoroughly combined. Add to flour mixture; stir until blended. Stir in nuts and butterscotch chips. (Dough will be stiff.)
Drop dough by level tablespoons onto greased baking sheets. Bake 7 to 10 minutes or until edges are lightly browned. Cool on baking sheet 1 minute; remove to cool on wire racks.