Add 3 cups of the flour. Wrap in plastic and refrigerate overnight. Preheat the oven to 325 degrees F. Cut off pieces of the dough and place on a lightly floured board. Use cookie cutters to cut the dough into shapes you desire. Place cookies on baking sheets and bake until they are light brown with slightly darker edges, about 12 minutes.
Transfer cookies to cooling racks to cool.
To make the icing, beat the egg white in a large bowl until frothy. Add the sugar, a cup at a time, mixing until the icing is glossy. Place in a pastry bag and pipe onto cookies. To coat the cookies with icing, add more lemon juice to the egg white mixture and brush over each cookie instead of piping. Each of the 72 cookies contains 62 calories and 1 gram of fat.