1. Heat oven to 350 degrees.
2. Bar: cut margarine into flour and sugar.
3. When crumbly press into and ungreased 9 x 13 pan.
4. Bake 10 min.
5. Cool 10 min.
6. Filling:
7. Combine ingredients. Mix well.
8. Spread over partially baked crust.
9. Return to oven
10. Bake for 15-20 min.
11. Cool Completely
12. Frosting:
13. Blend frosting ingredients till creamy.
14. Spread over cooled bars.