Dollop Biscoff onto a paper-lined plate or small tray, spreading into 1.25cm/1/2" thick discs. Freeze for 1 hour until firm.

Brown the butter in a silver saucepan over medium-high heat for 4 to 5 minutes until foamy and nutty. Immediately pour into a heatproof bowl and cool to room temperature (approximately 45 minutes).

Hand mix the cooled brown butter with sugar, then add the egg and vanilla. In a separate bowl, whisk together the dry ingredients and spices, then gradually add to the wet mixture. Fold in chocolate chips if using.

Portion the dough into 8 equal pieces. Flatten each piece, place a frozen Biscoff disc in the center, and carefully wrap the dough around it, sealing completely.

Refrigerate the stuffed cookie dough balls for 12-24 hours (minimum 2 hours).

Bake from fridge cold on lined trays at 180°C/350°F (170°C fan) for 19 minutes. If desired, top with more chocolate while hot.

Cool on the tray for 20 minutes before serving.

Enjoy your pure melty perfection!