Preheat your oven to 180ºC (355ºF). In a mixing bowl, combine all-purpose flour, powdered sugar, and a pinch of salt. Cut in room temperature butter until the mixture resembles coarse crumbs. Press the mixture firmly into the bottom of a lined 9-inch springform pan. Bake for 18 minutes or until golden brown, then remove from the oven and allow it to cool completely.

Lower the oven temperature to 160ºC (325ºF). In a large bowl, beat cream cheese and granulated sugar until smooth, about 3 minutes. Mix in sour cream, cornstarch, and vanilla extract until well combined. Add large eggs one at a time, mixing until just blended. Gently fold in the chopped Twix bars, ensuring they are evenly distributed, then pour the filling into the cooled shortbread crust.

Prepare a water bath by placing a larger baking dish filled with hot water on the oven rack below the cheesecake. Bake the Twix Cheesecake for 1 hour and 20 minutes, or until the edges are set but the center jiggles slightly. This technique prevents cracking, ensuring a silky smooth finish. Once baked, turn off the oven and let it cool for 1 hour with the door ajar.

After the cheesecake has cooled in the oven, transfer it to the refrigerator. Cover it loosely and chill for at least 6 hours, preferably overnight.

In a medium saucepan over medium heat, combine granulated sugar and corn syrup. Stir until the mixture is golden brown and fragrant, about 8-10 minutes. Carefully whisk in heated heavy cream gradually, continuing to stir until fully combined. Remove from heat and add cold butter and a pinch of salt, stirring until melted and silky. Let the caramel cool before using.

Once the Twix Cheesecake has set and the caramel is cool, carefully remove the cheesecake from the springform pan. Generously drizzle the silky caramel over the top, allowing it to cascade over the edges. Garnish with additional chopped Twix bars for an eye-catching presentation. Refrigerate briefly until ready to serve.