In a small bowl combine the flour and salt. Whisk to remove lumps.

In a medium bowl combine the butter, brown sugar, granulated sugar, and Biscoff butter. Mix until fully combined and smooth.

Fold in the flour mixture until just combined.

Fold in crushed Biscoff cookies.

Preheat oven to 350 degrees (F).  Press the batter into the prepared pan. Bake for 30-35 minutes.