Brown Sugar Shortbread

1 cup unsalted butter, softened
1 cup firmly packed light brown sugar
1 teaspoon vanilla extract
2 1/4 cups sifted all-purpose flour

Preheat the oven to 325 degrees F. Butter a 9-inch cake pan and set aside.

Beat butter, brown sugar and vanilla extract together until fluffy, about 3 minutes. Add flour in 4 batches and combine well after each addition. This can be mixed with your hands. Scrape the dough into the prepared pan and pat into an even layer. Prick the surface with the tines of a fork. Score the top (without cutting all the way through the dough), so that it will be easy to break apart into serving pieces. Bake in the upper third of the oven for about 30 minutes, or until the top is puffy and lightly browned.

Serves 8.