Mix flour, baking soda and salt together. In another bowl, beat softened butter, white sugar, brown sugar on med. speed till light and fluffy. TIP: If your butter is too cold, place in mirco for 24-45 seconds. Add egg and vanilla beat till well blended. Gradually add flour mixture, beating until well blended. Stir in chunks, peanut butter chips and walnuts. drop by heaping tablespoons onto ungreased baking sheet 2 inches apart. Bake 375° for 11-12 minutes or till lightly brown. Optional, sprinkle a little coarse sea salt on top just as you take them out of oven.
TIP: If you make a larger cookie, increase the baking time by a few minutes.