Preheat the oven to 350℉ / 180℃ and line your baking tray with parchment paper; set aside.
Mix the flour and salt together in a large bowl and keep aside.
In the bowl of stand mixer add the butter, sugar, and almond extract and beat them together on medium-high till the mixture turns creamy (2-3 min) (You can also use electric hand mixer for this).
Add in the egg and mix beat it's combined well.
Add in the dry mixture in batches and mix till it forms a dough.
Flatten the dough, wrap it with a cling wrap, and refrigerate for at least an hour.
Once chilled, take the dough out and let if rest for 5 minutes at room temperature. Roll out the dough on a lightly floured surface to ¼ inch thickness and cut out cookies using a 3-inch fluted round cookie cutter.
Cut out a smaller section in the middle for the Biscoff to beautifully show using the back of a moderately sized piping tip (1-1 ½ inch) from one of the two cookies.
Place the cutouts on the prepared baking tray and bake for 12-15 min in a preheated oven.
Let the cookies cool for 5 minutes in the baking tray before transferring them to a wire rack to cool completely.
Apply a generous amount of Biscoff spread on the cookie without the cut-out. and then place the cut-out cookie on top. Press gently to make a sandwich.
Enjoy!