Cut four 14 inchx12 inch pieces of waxed paper or plastic wrap. In a bowl, cream butter or margarine, sugar, and brown sugar. Beat in vanilla and eggs until light and fluffy. In a bowl, combine dry ingredients. Stir flour mixture into egg mixture until blended. Add chocolate chips and nuts. Divide dough into 4 pieces. Shape each piece into an 8 to 25 cm roll. Wrap rolls in waxed paper or plastic wrap. Place in a freezer container with a tight-fitting lid, or wrap airtight in a piece of foil. Label and date. Store in freezer. Use within 6 months.
To make cookies: Slightly thaw a roll of dough. Preheat oven to 180ºC . Cut dough into slices or chunks. Arrange pieces on an ungreased baking sheet about 4 cm apart. Bake 10 minutes until browned around edges. Remove and cool.