Preheat the oven to 350°F and wrap the outside of a 9-inch springform pan with two layers of heavy-duty foil. Mix the chocolate graham cracker crumbs with the melted butter, press into the bottom of the pan and bake for 10 minutes.
Let it cool, reduce the oven to 325°F and bring a kettle of water to a boil. Blend the cottage cheese in a food processor or blender for 2 to 3 minutes, scraping down the sides, until completely silky.
Add the cream cheese, peanut butter, brown sugar, cornstarch, vanilla and salt and blend until smooth and creamy. Add the eggs and pulse just until combined.
Pour the filling over the crust and tap the pan to release air bubbles. Set the springform in a roasting pan, add hot water about 1 inch up the sides and bake for 60 to 70 minutes, until the edges are set and the center jiggles slightly.
Turn off the oven, crack the door and let the cheesecake cool inside for 1 hour. Remove from the water bath, loosen the edge with a thin spatula, cool to room temperature and refrigerate for at least 6 hours.
Heat the heavy cream until steaming, pour it over the chopped chocolate and let it sit for 3 minutes. Stir until glossy, cool for 10 minutes, then pour over the chilled cheesecake and spread it to the edges.
While the ganache is still soft, arrange the peanut butter cup halves around the edge and drizzle with the warmed peanut butter. Chill for 30 minutes until set, then release the ring and serve.