This butter shortbread recipe is one that you will not be able to pass up. With Land O'Lakes butter and eggs, you’ll be using the best-quality ingredients.
Heat oven to 350 degrees F. Line an 8-inch square baking pan with aluminum foil. Spray foil lightly with nonstick cooking spray. Set aside.
Combine all crust ingredients in bowl; beat at medium speed just until mixture resembles coarse crumbs. Press dough evenly into bottom of prepared pan. Bake for 15 minutes. Remove from oven and cool for 10 minutes.
Combine water, corn syrup, and vanilla in small bowl; set aside.
Place 6 tablespoons butter, sugar, and salt into bowl; beat until well combined. Add egg; beat until well mixed. Add flour alternately with corn syrup mixture, beating until well mixed after each addition. Spread topping evenly over shortbread crust. Bake 25–30 minutes or until golden brown.
Cool completely. Remove from pan and sprinkle with powdered sugar, if desired.