Combine oats, flour, pecans, brown sugar, salt and baking soda, stirring well. Add butter and sitr or beat at low speed with an electric mixer until mixture is crumbly. Reserve 1 1/2 cups crumb mixture; press remaining crumb mixture into a lightly greases 15- x 10-inch jellyroll pan. (Mixture will be thin in pan.) Bake for 10 minutes. Cool in pan on a wire rack.