Beat Butter, sugars and eggs till fluffy. Add oil, miss till fluffy, Add Flour Cream of tartar, baking soda and vanilla and 2 cups of flour. Miss until combined, add remaining 2 cups flour and mix until combined. Add chocolate chips and nuts. Mix and drop by spoonfuls onto ungreased cookie sheet . about 1 in. apart.
Bake at 350 degrees in preheated oven for approx. 20 minutes.