Preheat your oven to 350 °F and line a standard cupcake pan with 18 liners. Mix together chocolate graham cracker crumbs, sugar, and melted butter until well blended. Then press about 1 tablespoon of crust into each liner using the bottom of a measuring cup to compact.
In a large bowl, beat the cream cheese until smooth. Add sugar, and mix until fully incorporated, then beat in eggs one at a time. Finally, add peanut butter and vanilla, mixing just until smooth—be careful not to overmix or introduce too much air.
Divide the filling among all 18 cups (about 3 tablespoons each). Tap the pan gently to settle. Bake for 17–19 minutes, until the centers only slightly jiggle. Turn off the oven, crack the door, and let the cheesecakes rest inside for 2–3 minutes before removing to cool further for 30 minutes.
In a small bowl, combine chocolate chips, peanut butter, and coconut oil. Melt in the microwave in 30-second increments (stirring each time) until smooth, or melt over a double boiler. Spoon the melted mixture over each cooled cheesecake, tilting the pan so the coating spreads to the edges.
Refrigerate the coated cheesecakes for at least 2 hours, up to 1 day, to allow the shell to firm up fully. Then they’re ready to enjoy!