BASE:

1 pkg. yellow cake mix (less 2/3 c.)
1/2 c. butter
1 egg

FILLING:

2/3 c. cake mix
1/2 c. brown sugar
1 1/2 c. dark corn syrup
3 eggs
1 tsp. vanilla
1 c. chopped pecans

Grease 9x13 inch pan. Mix yellow cake mix (less 2/3 cup), butter and egg until crumbly. Press into pan. Bake at 350 degrees for 10 to 15 minutes, until light brown.

Prepare filling, beating 1 to 2 minutes. Pour over partially baked crust. Sprinkle pecans over top, return to oven and bake 30 to 35 minutes.