1/2 cup (1 stick) unsalted butter, room temperature
1/2 cup sugar
1 teaspoon vanilla
2 1/2 cups flour
1/2 teaspoon salt
1 teaspoon baking powder
1 1/2 cup prepared mincemeat
2 egg whites for wash
With electric beater, cream butter and sugar until fluffy, then beat in the eggs and vanilla.
In a separate bowl, sift together the flour, salt and baking powder. Stir this into the butter mixture only enough to blend. Chill the dough 30 minutes or overnight. Remove one-quarter at a time; keep rest refrigerated. On a lightly floured surface, roll out the dough to 1/8-inch thickness.
Preheat oven to 375 degrees.
Cut the dough into rounds with a floured cookie cutter. Depending on how large you want to make each cookie, spoon between 1/4 and 1 teaspoon of mincemeat onto the center of each round. Place a second round on top and press the edges together with a fork. Prick the center of each cookie to allow steam to escape during baking. Whisk egg whites and brush on cookies.
Bake 10 minutes, depending on the thickness and diameter of the cookies. Remove the cookies from the pan while warm and cool on wire rack.
Makes 2 to 3 dozen cookies.
From Ron Krueger, food writer, Flint (Mich.) Journal