Brown 2 cups of brown sugar in skillet (large). Beat 2 egg yolks, add 1/2 cup water and beat again. Add 4 tablespoons flour and beat until smooth. Add 1 cup white sugar, 1 tablespoon vanilla, 1/4 teaspoon salt. Beat and then stir in 2 1/2 cups milk and add lump butter (about size of egg). Pour this into sugar mixture and stir, cook until smooth and well done. Pour into baked pie shells.