1. Preheat the oven to 325°F.

2. Prepare a 9-inch diameter springform pan with at least a 2 1/2-inch depth for a water bath. Place a large square of heavy-duty aluminum foil underneath the pan. Gently fold the edges up and around the pan. Repeat twice so there are three sheets of foil, to ensure a waterproof seal. Gently fold the top of the foil around the edge of the pan. Alternatively, use a turkey roasting bag to seal the pan from the water bath. Spray the pan with nonstick cooking spray.

Make the crust:

1. In the bowl of a food processor, combine the graham crackers, peanuts, sugar, and cinnamon until very finely ground. Add the butter and pulse until the mixture is moistened like wet sand. Press firmly into the bottom and quarter-way up the sides of the prepared pan. Bake for 10 minutes. Place on a wire rack to cool. Maintain oven temperature.

Make the filling:

1. In a large bowl, use an electric mixer to beat the cream cheese on medium speed until completely smooth and free of lumps, scraping down the bowl and paddle as needed. Add the peanut butter, sour cream, sugar, and flour and beat until combined. Scrape down the bowl and paddle completely, then blend again until combined and smooth. Add the eggs and yolk, one at a time, and beat until just combined. Be careful not to overmix.

2. Pour the batter into the prepared springform pan. It will fill almost completely to the top. Tap the pan against the counter a few times to release any air bubbles in the batter.

3. Place the pan in a larger roasting pan. Pour boiling water into the roasting pan until the water is about halfway up the sides of the cheesecake pan. This is usually best done once the pans are already on the oven rack, to avoid spilling boiling water.

4. Bake at 325°F for 1 hour, or until the top looks slightly dry and the middle is slightly wobbly. Err on the side of underbaking rather than overbaking.

5. Turn off the oven heat and open the oven door just by 1-inch. Sticking a wooden spoon in between the oven and the door can help with this. Let the cheesecake cool inside the oven for 30 minutes to 1 hour or until the oven is just warm. This will prevent cracks from forming.

6. Remove the cheesecake from the oven and from the water bath, unwrap the foil, and transfer it to a cooling rack. Run a thin-bladed flexible knife around the edge of the cheesecake to make sure it's not sticking to the sides (which can cause cracks as it cools). Let the cheesecake cool completely to room temperature on the rack.

7. Refrigerate until completely chilled, at least 6 hours but preferably overnight.

Make the peanut butter topping:

1. In a small saucepan, bring the cream to a simmer. Add the peanut butter and stir until it begins to melt. Remove from heat and stir vigorously until smooth. Allow to cool to room temperature. Pour over the chilled cheesecake. Return to fridge for about 15 to 30 minutes to allow topping to set before slicing and serving.

2. Store the cheesecake uncovered or very loosely covered to avoid condensation. Store for up to 5 days in the fridge.