Preheat oven to 375°F (190°C).
Beat butter, vanilla sugar, brown sugar and eggs with electric mixer on high until light and fluffy.
Stir in flour, salt and baking soda by hand. Blend well.
Stir in chocolate chips.
Drop by heaping teaspoonfuls onto un-greased cookie sheet 2" apart.
Bake 10 to 12 minutes, until lightly browned.
Transfer to cooling rack. Cool.
Tip: For best results, bake 1 cookie sheet at a time on middle oven rack.