1In small bowl, mix oats, flours, baking powder, baking soda and salt with whisk; set aside. In large bowl, beat butter, brown sugar and granulated sugar with electric mixer on medium speed until fluffy. Beat in egg and vanilla. Gradually add oat mixture, beating on low speed just until combined. Stir in chocolate chips and nuts.
2Shape dough into 16x1 1/2x1 1/2-inch log; wrap in plastic wrap. Refrigerate 1 hour or until firm.
3Heat oven to 350°F. Unwrap dough. Using serrated knife, cut dough into 1/2-inch slices. Place 2 inches apart on ungreased cookie sheet.
4Bake 9 to 11 minutes or just until edges are golden. Cool 2 minutes; remove from cookie sheet to cooling rack.