1. In a bowl, mix flour and brown sugar. Cut butter into chunks and add to bowl.
2. With a pastry blender, cut butter until mixture is crumbly and no large particles remain.
3. Press dough with your hands to form a ball, then pat evenly in an 8- or 9-inch-wide cake or cheesecake pan with removable rim.
4. With the tines of a fork, make impressions around edge of dough. Then pierce surface of cookie all over.
5. Bake in a 300° oven until slightly darker golden brown, about 40 minutes.
6. While hot, remove pan rim and cut cookie into 12 to 16 wedges. Sprinkle with granulated sugar. Cool on a rack.
7. Serve, or store airtight up to 1 week. Freeze to store longer.
Nutritional analysis per cookie.