First Step: Prepare Oven and Ingredients
Preheat your oven to 375°F (190°C). Line two baking sheets with parchment paper or silicone baking mats to prevent sticking and facilitate easy cleanup.

Second Step: Process Biscoff Cookies
Process 16 of the 32 biscoff cookies into fine crumbs (about 1 cup) using a food processor and set aside. Roughly break 8 cookies into chunky pieces to fold into the dough later. Reserve the remaining 8 whole cookies for decoration on top after baking.

Third Step: Cream Butter and Sugars
In a large mixing bowl, cream together the cold cubed butter with brown sugar and granulated sugar for 3-4 minutes until light, fluffy, and smooth. This step is essential for creating a tender cookie texture.

Fourth Step: Add Eggs and Vanilla
Mix in the eggs one at a time, beating well after each addition. Add the vanilla extract and scrape down the sides to ensure even incorporation.

Fifth Step: Incorporate Biscoff Cookie Butter
Stir in the biscoff cookie butter until well combined with the creamed mixture, infusing the dough with rich biscoff flavor.

Sixth Step: Combine Dry Ingredients
In a separate bowl, whisk together the all-purpose flour, biscoff cookie crumbs, cornstarch, baking soda, baking powder, and salt. Gradually add this dry blend to the wet ingredients and mix just until combined, avoiding overmixing to retain softness.

Seventh Step: Add Chunks and White Chocolate Chips
Fold in the roughly broken biscoff cookie chunks and white chocolate chips evenly throughout the dough to create flavorful pockets and a delightful texture.

Eighth Step: Portion and Stuff Dough
Using a ¼-cup scoop, portion dough into large balls for generous cookies. For stuffed cookies, split each ball in half, create an indentation in one half, spoon about 2 teaspoons of extra biscoff cookie butter inside, and seal with the other half. Optionally, roll gently for even size and uniform shape.

Final Step: Bake, Decorate, and Cool
Place the dough balls spaced well apart on the baking sheets and bake for 8-10 minutes until edges are set but centers remain slightly underbaked for softness. Immediately after baking, press half a reserved whole biscoff cookie and a few white chocolate chips on top for visual appeal and extra flavor. Allow cookies to cool on the sheets for 10 minutes, then transfer to a wire rack to cool completely before serving.