1. Sift flour and baking soda.
2. Mix brown sugar and margarine until crumbly.
3. Stir into flour, add coconut and oats.
4. Press firmly into a 9x13 pan.
5. Mix eggs, chocolate chips, brown sugar, walnuts, margarine and flour.
6. Pour over base.
7. Bake at 350 degrees for 35 minutes.