Preheat the oven to 350 degrees. If your oven heats more pr less than normal, account for that by slightly changing the temperature.
Lightly grease a 9 x 14 inch pan
In a mixing bowl, beat together the butter, brown sugar, eggs and vanilla until smooth.
Add the flour mixture to the egg mixture and beat until we'll blended.
Spread the batter evenly in the prepared baking pan.
In a small bowl, combine the white sugar and cinnamon.
Sprinkle the sugar and cinnamon evenly over the batter in the baking pan.
Bake for 25 - 30 minutes or until the surface springs back when gently pressed. Depending on the type of baking pan (glass, metal, etc.) you may have to change the amount of baking time needed.
Remove from the over and let cool slightly.
While still warm, cut into squared with a sharp knife.