1. Preheat oven to 350°.
2. Combine first 7 ingredients in a large bowl; stir until well combined. Weigh or lightly spoon flour into a dry measuring cup; level with a knife. Add flour, oats, nuts, and chocolate chips to sugar mixture; stir until just combined.
3. Scrape the dough into a 9-inch glass pie plate coated with cooking spray, and spread to edges using a spatula. Bake at 350° for 13 minutes or until set. Cool slightly on a wire rack. Cut into 8 wedges.