Prepare your coffee using your preferred method (espresso machine, French press, or strong drip). Extract exactly 1/2 cup of a very strong, dark brew. Pour the steaming hot coffee directly into a large, heat-proof glass or your favorite oversized ceramic mug.
While the coffee is still visibly steaming, drop your room-temperature cookie butter directly into the center of the mug. Add the packed brown sugar and vanilla extract. Use a small metal whisk or a fork to stir the mixture vigorously until the thick spread dissolves completely, leaving no clumps at the bottom.
Pour your cold milk into a microwave-safe glass mason jar, leaving plenty of empty room at the top. Heat the jar in the microwave for exactly 60 seconds, or until it reaches about 150°F (65°C). Carefully secure the metal lid tightly onto the hot jar. Wrap a kitchen towel around the glass to protect your hands, and shake the jar aggressively for 30 to 60 seconds until a thick, frothy foam forms. (Alternatively, use a handheld milk frother or steaming wand).
Use a large spoon to hold back the thick top layer of foam in the jar, and slowly pour the warm, liquid milk into your spiced coffee base. Once the mug is nearly full, gently scoop the thick, airy foam directly onto the top of the liquid.
Dispense a tall swirl of sweet whipped cream directly over the milk foam. Crush your crispy Lotus biscuits in your hands, letting the crumbs fall over the whipped cream. For an extra touch, drizzle a small amount of melted cookie spread right over the top. Serve immediately!