Layered Ice Cream Dessert

Sprinkle 1/2 cup cookie crumbs evenly in ungreased 13 x 9 inch pan. Set aside. Combine butter and chocolate in saucepan, cook over low heat until melted. Remove from heat. Add powdered sugar and beat 2 minutes at medium speed of electric mixer. Add yolks, beating until smooth. Beat egg whites (at room temperature) until stiff peaks form. Fold into chocolate mixture carefully. Spoon mixture over crumbs, and sprinkle with pecans. Cover and freeze until firm. Spread softened ice cream over pecans. Sprinkle with remaining 1/4 cup crumbs.