01 - Preheat oven to 325°F (160°C). Grease and line the bottom of a 9-inch springform pan with parchment paper.
02 - Combine crushed chocolate cookies and melted butter until fully incorporated. Press mixture evenly into the bottom of the prepared pan. Place crust in freezer while preparing other components.
03 - In a mixing bowl, cream together softened butter, brown sugar, and granulated sugar until pale and fluffy. Beat in milk and vanilla extract. Add heat-treated flour and salt, mixing just until dough forms. Gently fold in mini chocolate chips.
04 - Roll most of the cookie dough into marble-sized balls, reserving a portion if desired for garnishing. Refrigerate dough balls until ready to assemble.
05 - Using an electric mixer, beat softened cream cheese and granulated sugar until smooth and creamy. Add eggs one at a time, mixing well between each. Blend in sour cream, vanilla extract, and flour, mixing just until combined.
06 - Pour half of the cheesecake batter over the prepared crust. Scatter half of the cookie dough balls across the batter. Top with the remaining cheesecake batter and smooth surface. Distribute reserved cookie dough balls on top, if using.
07 - Bake on center rack for 55 to 65 minutes, or until cheesecake edges are set and center is just slightly wobbly. Turn oven off, crack oven door open, and allow cheesecake to cool inside oven for 1 hour.
08 - Remove cheesecake from oven and let cool completely at room temperature. Refrigerate for a minimum of 4 hours or overnight until thoroughly chilled.
09 - Before serving, sprinkle with mini chocolate chips and extra cookie dough balls. Slice and serve chilled.