Melt semi sweet chocolate morsels in a microwave safe bowl for 1 minute. Stir until smooth (if needed, heat an additional 15-30 seconds). Set aside to cool.
To make the filling, mix the softened cream cheese, cocoa powder and sugar in a large mixer bowl until combined well.
Add the sour cream and vanilla extract and mix until well combined. Set aside.
In another large mixer bowl, add the heavy whipping cream and powdered sugar and whip on high speed until stiff peaks form or you can use Cool Whip if you wish.
Add in cooled down melted chocolate and mix until smooth and fluffy.
Carefully fold the whipped cream into the cheesecake filling.
Divide the filling between the 12 cheesecake cups until the cups are full. It's easy to use a large piping bag to add the filling, but spooning it in would work as well.
Refrigerate cheesecake for 4 hours, or overnight.
Before removing cheesecakes from the springform pan, slide a butter knife around the edges of the Mini-Cheesecakes first for easy removal and slide the bottoms upward to release the cheesecakes.. Or remove the cheesecakes from their wrappers, if desired for serving.