01 -
Preheat the oven to 325°F (165°C) and grease a 9-inch springform pan with non-stick spray. Combine the brownie mix, vegetable oil, water, and egg in a medium bowl. Stir approximately 50 times to combine (the batter may be slightly lumpy). Spread the mixture into the prepared pan.
02 -
Bake the brownie base for 25 minutes or until a toothpick inserted in the center comes out clean.
03 -
While the brownie is baking, prepare the cheesecake filling. In a large bowl, using a hand or stand mixer, blend the cream cheese, sugar, peanut butter, and vanilla extract until smooth and creamy. Add the eggs one at a time, mixing on low speed between each addition until just incorporated. Refrigerate until ready to use.
04 -
Once the brownie bottom is baked, pour the peanut butter cheesecake mixture on top and spread the surface evenly with a spatula. Raise the oven temperature to 350°F (175°C).
05 -
Bake the cheesecake for 45-50 minutes or until the center is almost set. Check at 35 minutes for doneness. The center should slightly jiggle only within a small circle when done. Cool on the counter for 10 minutes, then refrigerate for a minimum of 3 hours before serving.
06 -
Before serving, melt the chocolate chips and peanut butter together in a microwave-safe bowl. Heat for 30 seconds, stir, then heat for an additional 20 seconds if needed until smooth. Transfer to a plastic bag, snip off the tip, and drizzle over the cheesecake.
07 -
Slice the cheesecake and serve chilled.