01 - Preheat oven to 350°F. Line a 9-inch square baking pan with parchment paper, leaving an overhang for easy removal.
02 - In a microwave-safe bowl, melt the butter. Whisk in sugar, eggs, and vanilla until glossy. Sift in flour, cocoa, and salt. Mix just until combined. Spread evenly in the pan.
03 - With an electric mixer, beat cream cheese and sugar until smooth. Add eggs one at a time, beating well, then add vanilla and sour cream. Pour evenly over the brownie layer.
04 - Bake for 45–50 minutes or until the center is just set and edges are lightly golden. Cool completely at room temperature, then chill for at least 2 hours.
05 - In a saucepan or microwave, melt caramels with heavy cream, stirring until smooth. Pour over chilled cheesecake and spread gently.
06 - Chill an additional 30 minutes until caramel is set. Slice into bars and serve.