Scrape into the prepared pan and spread into an even layer with a spatula. Bake 20 to 25 minutes until lightly browned and firm, and a knife inserted in the center comes out clean. Let cool then cut into shapes or bars. (If using a cookie cutter to cut shapes, trim the excess from around each shape and use a pancake turner to lift the shape from the pan.) Drizzle with melted white chocolate and/or butterscotch chips, if desired, and serve.