Preheat oven to 350. In a larger mixing bowl, cream the butter, sugars, eggs and vanilla well. Sift together the flours, salt baking power and baking soda. Combine the wet and dry ingredients. Stir in the chocolate chips. With your fingers place golf ball size dough portions 5 cm apart on an ungreased cookie sheet. Bake 9 minutes or until edges are light brown. NOTE: It is very important you not exceed the cooking time given above, even if the cookies appear to be underbaked.When the cookies are removed from the oven the sugar in them will stay hot and continue the cooking process. The finished product should be soft in the middle and crunchy around the edges. For variation of this cookie substitute milk chocolate for the semi sweet chocolate and or add 1.5 cups chopped walnut walnuts or macadamia nuts to the recipe before baking.Although you can sub margarine for butter you will have the best results from butter. The cookie will have a richer taste and will be crisper around the edges like the original.