Directions:
Preheat the oven to 350 degrees. Butter and lightly flour a 13 x 9 inch baking pan.
Beat the butter and both sugars in a large mixing bowl until light and fluffy. Add the egg, vanilla, flour, salt, and baking soda and mix until well blended.
Spread the batter in the prepared pan. Bake 25 to 30 minutes. Let cool in the pan completely before cutting.