Cream the extra Biscoff spread, butter and brown sugar with hand-held beaters or a stand mixer on medium/high speed for 3-4 minutes. Add the egg and vanilla extract and beat again on medium speed until combined.
Roll the dough around the frozen cookie butter to fully enclose it. Press a piece of chopped Biscoff biscuit into the top of each dough ball.
Bake Biscoff cookies for 10-12 minutes