Step 1

Lightly grease an 8x8'' baking pan.*

Step 2

Preheat oven to 350 degrees F.

Step 3

Combine topping ingredients together in a bowl. Set aside.

Step 4

In a mixing bowl cream together butter and sugar until pale and fluffy. Add egg and mix. Add sour cream and vanilla and mix.

Step 5

In a separate bowl whisk together the flour, baking soda and baking powder.

Step 6

Add dry ingredients to butter mixture and mix just until combined.

Step 7

Spoon half of the batter into your prepared pan and smooth into an even bottom layer.

Step 8

Sprinkle half of the topping mixture over the top. Spoon remaining batter on top and smooth into an even layer.

Step 9

Sprinkle remaining topping mixture over the top.

Step 10

Bake in preheated oven for 35-45 minutes or until a toothpick inserted into the center comes out clean, or with few crumbs.

Step 11

Check the mixture about half way through baking --you may want to put a piece of tinfoil over the top to keep the top from browning too much.

Step 12

Allow to cool for at least 10 minutes before serving.