Preheat the oven to 350º F. Line a regular sized muffin pan with paper muffin liners. In a mixing bowl, combine the graham cracker crumbs and melted butter until it resembles coarse sand. Put 1-2 tbsp of  crumbs in each muffin cup. Use a 1/3 cup (or similar) to press the crumbs down firmly into the pan. Bake the crust for 5 minutes. Remove the pan from the oven and allow it to cool while prepping the cheesecake.

In a mixing bowl, beat the cream cheese, peanut butter and sugar with an electric mixer until smooth, 1-2 minutes.

Beat in vanilla extract and eggs, one at a time, until smooth. The eggs are the last ingredient that get mixed into the cheesecake batter. Be sure to mix them in, one at a time, just until the yolk breaks. Over beating the eggs is the number one cause of air bubbles and cracking.

Evenly divide the cheesecake batter among the muffin cups, filling the liners full. Bake for 15-17 minutes or until the center of the cheesecake is only slightly jiggly.

Allow the cheesecakes to cool to room temperature then place them in the fridge for at least 4 hours to chill before serving. If refrigerating overnight, loosely cover the cheesecakes in plastic wrap.

Place the chocolate chips in a medium bowl. In a small pot over low heat, heat the heavy cream until just before boiling. Pour the heavy cream over the chocolate chips. Allow the mixture to stand for 1-2 minutes. Use a spatula to stir the mixture until smooth. Allow the ganache to come to room temperature before adding it to the cheesecake. Spoon ganache onto each cheesecake and top with chocolate shavings.