Preheat oven to 350 degrees F.
Combine flour, sugar, and salt in a bowl. Cut in margarine until mixture resembles coarse meal. Press crust into ungreased 10 by 15-inch baking pan. Bake for 15 minutes or until golden brown.
Mix eggs, nuts, brown sugar, and coconut until well blended; spread over baked crust.
Bake an additional 30 minutes or until set.
While still warm, loosen the edges with a metal spatula. Mix together the powdered sugar, lime juice, and zest with a fork. Working quickly, spread the lime paste all over the top with a spatula while still warm. Let cool to room temperature and cut into bars. Cut 11 cuts crosswise and 3 cuts lengthwise.
A viewer or guest of the show, who may not be a professional cook, provided this recipe. It has not been tested for home use.