01 - In a large mixing bowl, beat the softened butter with powdered sugar using an electric mixer on medium speed until light and fluffy, about 2 minutes.
02 - Add the lemon zest and vanilla extract to the creamed mixture and blend until thoroughly combined.
03 - Sift together the all-purpose flour and salt. Gradually add the dry mixture to the wet ingredients, mixing on low speed until a soft dough forms.
04 - Divide the dough into two equal portions. Flatten each into a disc, wrap in plastic wrap, and refrigerate for 30 minutes to firm.
05 - Preheat oven to 350°F (175°C). Line two baking sheets with parchment paper.
06 - On a lightly floured surface, roll out the dough to 1/4-inch thickness. Cut shapes using a 2-inch cookie cutter. Arrange half of the cookies on the prepared baking sheets.
07 - Using a smaller cutter, remove the centers from half of the cookies to create tops for the sandwiches.
08 - Bake for 11 to 13 minutes, or until the edges are just beginning to turn golden. Allow cookies to cool completely on a wire rack.
09 - Stir fresh lemon juice into raspberry jam until smooth and combined.
10 - Spread about 1/2 teaspoon of the raspberry-lemon filling onto the flat side of each solid cookie. Top with a cutout cookie and gently press to adhere.
11 - If desired, dust the finished cookies with powdered sugar just before serving.