In a mixing bowl, combine cold butter and cream cheese, mixing until smooth. Add vanilla extract and gradually incorporate all-purpose flour. Mix until the dough binds together, forming a ball. Wrap in plastic wrap and chill for 1 hour.

Preheat your oven to 375°F (190°C) and line baking sheets with parchment paper.

Lightly flour your work surface and roll the dough to an even thickness of ⅛ inch. Cut the dough into 2x2 inch squares.

Place about 1/4 teaspoon of your chosen fruit filling into the center of each square and bring the opposite corners together to seal.

Arrange the filled cookies on the prepared baking sheets and bake for 12-15 minutes until lightly golden and puffy.

Let the cookies cool on a wire rack, then dust with confectioners' sugar before serving.