For the crust:
Preheat the oven to 350°F. Line an 8 by 8-inch baking pan with foil and spray with nonstick cooking spray.
Combine the pretzel crumbs, melted butter, and sugar. Press the mixture into the bottom of the prepared pan, using the bottom of a glass or measuring cup to pack very firmly into the pan. Bake for 10 minutes. Remove from oven and sprinkle with the chocolate chips. Bake for another 2 minutes. Remove from oven and smooth the melted chocolate chips with an offset spatula. Let cool completely.
For the filling:
In the bowl of an electric mixer, beat the cream cheese and sugar on medium-high speed until well combined and smooth. Beat in the eggs, one at a time, until combined. Add in the peanut butter, vanilla, and salt and beat until just combined. Pour over the cooled crust.
Bake at 350°F for 30 minutes, or until the cheesecake is set at the edges but ever so slightly jiggly in the middle. Cool completely in the pan on a wire rack. Cover and chill the cheesecake in the fridge until very cold, at least 3 hours. The cheesecake can be stored in the fridge for up to 2 days.
For the topping:
Place the cream in a glass measuring cup. Microwave for 25 seconds, or until steaming hot but not bubbling. Add in the chocolate chips and peanut butter. Let sit for 2 minutes. Stir until smooth. Remove to a zip-top bag, snip a very small hole in one corner, and drizzle over the cheesecake. Serve or refrigerate.