Preheat your oven to 350°F (175°C). In a mixing bowl, combine crushed chocolate cookies and melted butter, mixing until the crumbs are well-coated. Press this mixture firmly into the bottom of a springform pan, creating an even layer. Bake for about 10 minutes until set, and then allow to cool completely while preparing the filling.

In a large mixing bowl, beat the softened cream cheese and granulated sugar together until smooth and creamy, about 3-4 minutes. Gradually add in the sour cream until fully incorporated. If desired, add a splash of vanilla extract.

Gently fold in toffee bits and chocolate chips into the cream cheese mixture using a spatula. Be careful not to overmix.

Wrap the outside of the springform pan with wet dish towels to prevent cracking while baking. Place inside a larger baking dish and fill it with hot water. Bake in the preheated oven for 50-60 minutes. The edges should be set, while the center jiggles slightly.

Once baked, turn off the oven and leave the cheesecake inside with the door slightly ajar for 30 minutes. After that, carefully remove it from the water bath and refrigerate for at least 4 hours or overnight to chill.