Preheat oven to 350 degrees. Generously coat the bottom and sides of a 13" x 9" pan with non-stick cooking spray.
In a medium bowl, use an electric hand mixer to blend together softened butter, 2 cups flour and 1/2 cup white sugar. Mix for about 3 minutes until the mixture resembles coarse crumbs. Press into the bottom of the prepared pan pan. Bake for 17 to 20 minutes or until lightly golden at the edges. If using a metal pan, baking time will be near the lower end of the range.
Meanwhile, in a large bowl mix together the eggs, corn syrup, 1/2 cup white sugar, 1/2 cup brown sugar, 2 tablespoons melted butter, and vanilla until smooth. Stir in the chopped pecans and cashews. Spread the filling evenly over the crust as soon as it comes out of the oven. Sprinkle Delightfulls morsels evenly over the top.
Return to oven and bake for an additional 25 to 30 minutes in the preheated oven, or until center is set and edges are just beginning to caramelize.
Allow to cool completely before slicing.