Combine flour, baking soda and salt. Stir into peanut butter mixture. Press into prepared pan. Dough should be level with or slightly below edge of pan. Bake 8 to 10 minutes or until lightly browned.
Place cookies on wire racks positioned over waxed paper.
Cool cookies completely. Melt candy wafers according to package directions. Pour over cooled cookies. Refrigerate until set. Store at cool room temperature.