Preheat oven to 375. Lightly grease two 30 cm pizza pans. Cream butter, sugars, cream cheese and vanilla in large bowl. Add eggs, beat until light. Combine flour, baking soda and salt in small bowl. Add to creamed mixture; blend well. Stir in chocolate chips and walnuts (if used) Divide dough in half, spread each half evenly into prepared pans. IMPORTANT DO NOT SPREAD ALL THE WAY TO EDGES, THIS DOUGH DOES SPREAD Leave about a 1 cm space between edge of dough and rim of pizza pan. Bake 20 to 30 minutes or until lightly browned. Cool completely in pans on wire racks. To serve: cut into slim wedges. Personal note: When these were brown and ready to take out of the oven they had a soft consistency much like that of a soft batch cookie. I wanted a firmer cookie. Put them both back in the oven, and turned the off. Let sit for 1 hour hoping they then became more like a chocolate chip cookie. They never crisped up, but remained soft. Still tasted good.