Add milk, ice cubes, Biscoff spread, and 4 scoops of vanilla ice cream to a blender. Blend on high speed for 30-45 seconds until completely smooth and creamy.

Microwave 2 tablespoons of Biscoff spread for 15-20 seconds until melted and easily pourable.

Prepare your serving glasses by drizzling the inner walls with the melted Biscoff spread in a decorative pattern.

Using a butter knife, spread a thin layer of regular Biscoff spread around the top rim of each glass.

Crush 2-3 Biscoff cookies into fine crumbs and gently press them onto the spread-coated rim to create a cookie crust edge.

Place 1 scoop of vanilla ice cream at the bottom of each prepared glass.

Pour the blended milkshake into the glasses, leaving about 1 inch of space at the top.

Top with a generous swirl of whipped cream and drizzle with remaining melted Biscoff spread.

Garnish each glass with half a Biscoff cookie inserted at an angle.