Add eggs one at a time beating between each addition.
Add flour, lemon rind and baking soda gradually.
Stir in ½ cup of concentrate (reserve ¼ cup lemonade concentrate for glaze).
Drop dough 2” apart on to an ungreased cookie sheet.
Bake at 375 for 8 to 10 minutes or until lightly browned. Brush with reserved concentrate and sprinkle with sugar.
Note: It may take a few times to get this recipe right as the bottom of this cookie needs to be browned...but they can go from browned to burned easily. They are definitely worth the trouble! (I use an air cushion cookie sheet, which makes it easier.)