1 cup butter, softened
1/2 cup white sugar
1/2 cup corn syrup
2 eggs
1 teaspoon vanilla extract
2 cups all-purpose flour
4 teaspoons baking powder
1 cup white sugar
1 cup all-purpose flour
1 teaspoon baking soda
1 dash salt
1/4 teaspoon ground cinnamon
Preheat oven to 350 degrees F (175 degrees C). Lightly grease a 9x13 inch pan.
In a large bowl, cream together the butter, sugar, corn syrup, eggs, vanilla, white sugar, flour, baking powder and salt until smooth. Mix in the eggs, one at a time, then stir in the flour mixture. Mix all together until well blended. Fold in the flour mixture. Spread evenly into the prepared pan.
Bake at 350 degrees F (175 degrees C) for 1 hour, or until a toothpick inserted into the center of the cake comes out clean. While the cake is still warm, place the toothpick on the bottom of the pan and press down to release the butter mixture. Let cool completely before cutting into squares.