Preheat your oven to 350°F (175°C). In a medium mixing bowl, combine the graham cracker crumbs, sugar, and melted butter. Press into the bottom of a 9-inch springform pan. Bake for 8-10 minutes until golden brown and let cool.

In a large mixing bowl, beat the softened cream cheese with granulated sugar until smooth. Add sour cream, eggs, and vanilla extract, mixing until just combined. Pour this mixture over the cooled crust.

Bake at 350°F (175°C) for 50-60 minutes, allowing the edges to set but keeping the center slightly jiggly. Turn off the oven and crack the door, letting it cool slowly inside for about an hour.

In a separate bowl, cream together the softened butter and brown sugar until light and fluffy. Stir in flour and a splash of milk to achieve a doughy consistency. Fold in semi-sweet chocolate chips.

Once the cheesecake has cooled completely, spread the cookie dough layer on top. Press down gently. Wrap in plastic wrap and chill in the refrigerator for at least 4 hours, or overnight.

Remove the springform pan sides and slice the cheesecake. Garnish with whipped cream or extra chocolate chips if desired.