Preheat your oven to 350°F (175°C) and grease a 9-inch springform pan. Prepare your brownie mix according to package instructions, ensuring a rich chocolate flavor. Pour the batter into the pan and bake for 20-25 minutes, or until a toothpick inserted comes out with moist crumbs. Allow the brownie base to cool completely while you make the cheesecake layer.

Lower the oven temperature to 325°F (160°C). In a large mixing bowl, beat the softened cream cheese and granulated sugar together until smooth and creamy. Gradually add in the vanilla extract, then incorporate the eggs one at a time, mixing well after each addition. Finally, stir in the sour cream and heavy cream until everything is fully blended and silky.

With your cheesecake mixture ready, drizzle caramel sauce over the top in a zigzag pattern for that classic swirl effect. Take a knife and gently swirl it into the cheesecake filling without over-mixing, aiming for a beautiful marbled look.

Pour the cheesecake mixture carefully over the cooled brownie base, smoothing the top with a spatula. Bake in the preheated oven for 50-60 minutes, until the edges are set but the center jiggles slightly when shaken. Turn off the oven and let the cheesecake cool inside for 1 hour.

Transfer the cheesecake to the refrigerator and let it chill for at least 4 hours, or preferably overnight. Once ready to serve, carefully remove the cheesecake from the springform pan and garnish with caramel sauce, whipped cream, and optional chocolate shavings.