Preheat oven to 350°. Grease an 11″x 15″ baking pan.
Mix butter, sugar, oil, eggs, and milk with an electric mixer. Mix in vanilla. Add flour, salt, and baking soda, and mix well.
Pour batter into prepared pan. Spread evenly with off-set spatula or knife. Sprinkle with cinnamon sugar.
Bake 20 minutes, or until edges are light brown. Allow to rest for 10 minutes. Then, cut into squares.
*To make cinnamon sugar, mix 1/2 tablespoon ground cinnamon for every 1/4 cup granulated sugar.