01 -
Cream butter, shortening, and brown sugar together in a large bowl using a mixer on medium speed until mixture is light and fluffy, about 5 to 7 minutes. Add eggs one at a time, mixing thoroughly after each addition. Incorporate vanilla extract.
02 -
In a separate bowl, whisk together the all-purpose flour, baking soda, and salt. Gradually add the dry ingredients to the creamed mixture, mixing until a uniform dough forms.
03 -
Divide the dough in half. Shape each portion into a disk, cover securely with plastic wrap, and refrigerate until the dough is firm enough to roll, approximately 30 minutes.
04 -
Preheat oven to 350°F (175°C). On a lightly floured surface, roll one portion of dough to about 1/8 inch thickness. Cut rounds using a cookie cutter, placing half of the rounds on baking sheets lined with parchment paper.
05 -
Place about 1/2 teaspoon of seedless blackberry spreadable fruit in the center of each cookie round on the baking sheet. Top with remaining dough rounds, sealing edges gently. Optionally cut a small 'peekaboo' opening in the top cookie before sealing.
06 -
Bake in preheated oven until lightly golden, 10 to 12 minutes. Remove cookies from baking sheets and transfer to wire racks to cool completely.