1. Preheat the oven to 325º F.
2. Line a regular sized muffin pan with 12 muffin liners.
3. Blend the Oreos in a food processor until they resemble fine crumbs. In a mixing bowl, mix together the Oreo crumbs and melbed butter until well combined.
4. Divide evenly into each muffin cup. (I like to use a small scoop, like a melon ball scooper).
5. Use the bottom of  1/4 cup measuring cup to press the crumbs down firmly into the pan.
6. Bake the crust for 5 minutes. Remove the pan from the oven and allow it to cool while you prepare the cheesecake filling. 

Cheesecake Filling:

1. In a mixing bowl, beat the cream cheese with an electric mixer until smooth, 2-3 minutes.
2. Beat in the sour cream, granulated sugar, vanilla extract, and melted chocolate until smooth.
3. Beat in the eggs, one at a time on low speed, mixing just until barely combined. Once both eggs have been added to the cheesecake batter, beat for only 30-60 seconds, on medium low speed until the eggs are fully incorporated.
4. Divide mixture evenly among each muffin cup (they will be full). 
5. Bake for 20 minutes or until the center of the cheesecakes are only slightly jiggly.
6. Remove from oven and place muffin tin on a cooling rack. Allow the cheesecakes to cool to room temperature while still in the muffin tins. Place them in the fridge for at least 4 hours to chill (overnight is best) before serving. 
7. Top with chocolate ganache layer.

Chocolate Ganache:

1. Add chocolate chips and heavy cream to a medium microwave safe bowl. Heat in 15 second intervals until fully melted, stirring in between until smooth. 
2. Spread over chilled mini cheesecakes.