Preheat the oven to 350F. Line a mini muffin tin with mini cupcake liners and set aside.

To start the cheesecake layer, with a standing or handheld mixer, whip the cream cheese for about a minute until light and fluffy. 

Add the sugar and whip for another minute before adding the egg. Beat until well incorporated. Finally, mix in the sour cream and whipping cream until everything is well incorporated. Set aside. 

To make the brownie layer, place the chocolate chips and butter in a microwave-safe bowl. Melt until the chocolate and butter are smooth and mixed together. 

Mix the sugar and vanilla into the butter and chocolate, and then add each egg, one at a time, beating after each addition. 

Fold in the flour, cocoa powder and salt until everything is well incorporated. 

To assemble the brownie cheesecake bites, pour brownie batter into each one of the mini muffin cups, filling about 2/3 of the way full.

Then, top each cup off with cheesecake, filling almost to the top. If desired, swirl the brownies and cheesecake together. 

Slide the muffin tin into the oven, and bake for about 15 minutes, or until the cheesecake is set on top. 

Cool the bites in the mini muffin tin for about 5 minutes before removing them to cool on a wire rack. Repeat steps 7-9 if you have more batter remaining. 

Serve warm or chilled!