In a large bowl, blend together butter and brown sugar until fluffy. Add eggs, one at a time, mixing thoroughly. Stir in vanilla. Add dry ingredients and nuts; mix well. Take out one cup of dough and tint orange. Form remaining dough into 2 logs, tucking the colored dough in the middle of each log; wrap in wax paper, then in aluminum foil. Refrigerate overnight. Slice dough 1/4-inch thick; add chocolate chip eyes. Place on ungreased baking sheets. Bake at 350 degrees for 10 to 12 minutes.