Preheat oven to 350°F. Mix flour, cinnamon and salt in medium bowl. Set aside. Beat butter, sugar and vanilla in large bowl with electric mixer on medium speed until light and fluffy. Gradually beat in flour mixture on low speed until well mixed. Stir in oats.
Crumble into large pieces onto 2 foil-lined 15x10x1 inch baking pans.
Bake 12 to 15 minutes or until crisp. Cool completely on wire rack. Stir in raisins and walnuts. Store in airtight container up to 1 week.