First layer:
Mix together flour and margarine; add chopped nuts. Press into bottom of 9 X 13 inch pan; bake at 350 approximately 20 minutes until lightly browned. Cool

Second layer:
Cream together powdered sugar and cream cheese; fold into this mixture the Cool Whip. Spread on top of first layer.

Third layer:
Mix pudding mixes with milk; when it begins to thicken, spread on top of previous layer.

Top layer:
Spread Cool Whip on top of third layer; sprinkle with shaved chocolate if desired.