Melt butter in a mid size pot,And take off heat, let cool.
Stir in both Sugars and Vanilla and mix well.
Put eggs in a separate bowl and beat well.add to cool butter and sugar mixture.mixing well.
Then pour in flour, stir until well incorporated then stir in pecans , mixture will be thick. pour batter into greased pan, at least 2 inches deep and 13 inches long.bake at 350 until golden brown and tooth pick comes out clean in center. about 30 to 40 minutes.cut into squares while warm.