Start by finely chopping your white chocolate and placing it in a heatproof bowl. Heat the heavy cream until it simmers, then pour it over the chocolate. Stir until smooth, then add Biscoff spread and refrigerate for at least an hour.

Combine almond flour, powdered sugar, and crushed Biscoff cookies in a food processor. Pulse for about 30 seconds, then sift the mixture to remove clumps.

In a clean mixing bowl, whip egg whites on medium speed. Gradually add granulated sugar and whip until stiff peaks form, about 5-7 minutes.

Gently fold the sifted dry ingredients into the whipped egg whites in three increments until shiny and flowing. Avoid over-mixing.

Pipe even circles of batter onto a baking mat or parchment-lined sheet, aiming for uniform size. Tap the tray to release air bubbles.

Tap the trays on the countertop to release any air bubbles. Allow the macarons to rest until a skin forms, about 30-45 minutes.

Preheat the oven to 145°C (290°F) and let the macarons rest until touch-dry. Bake for 14-15 minutes until firm and lifted easily off the mat.

Once cooled, pipe a dollop of ganache on one macaron, add a dot of Biscoff spread, and sandwich with a second macaron.