1/3 pound unsalted butter
8 teaspoons sugar
1 teaspoon minced lemon zest
1 teaspoon minced orange zest
1 teaspoon Grand Marnier liqueur
1 cup all-purpose flour
pinch of salt
Place butter and sugar in an automatic mixer and beat on slow for 2 minutes. (Or mix with a hand-held mixer for at least 3 minutes.)
Scrape down the sides and beat on high for 3 minutes or until the batter is light in color and fluffy. (For 4 minutes if with a hand-held mixer.) Add lemon zest, orange zest, and Grand Marnier. Beat on high for 20 seconds. Then add flour and salt and beat for 1 minute.
Wrap dough in plastic and roll on a flat surface into a cylinder 6 inches long by 1 1/2 inches in diameter. Refrigerate for 2 hours.
Preheat oven to 325 degrees. Remove dough from refrigerator and cut into 12 slices 1/2 inch thick. Place on a baking sheet and cook for 16 to 18 minutes. Makes a dozen cookies.