Cream together sugar and margarine. Add egg yolks and 1 whole egg. Sift together and add flour and baking powder. Add vanilla.
Grease 10-by-15-inch cookie sheet or bread pan. Pat stiff dough on baking sheet.
Beat egg whites. Add brown sugar (with any lumps crushed). Spread over uncooked dough. Next, sprinkle the cherries and pecans on top.
Bake for 25 minutes at 325 degrees. Cut in squares when cool. Store in air tight container, with wax paper between layers. Freezes well.