Chocolate Marble Cheesecake

Instructions

1. Prepare the crust
   Preheat oven to 325°F (165°C). Mix graham cracker crumbs, melted butter, and 3 tablespoons sugar in a bowl until combined. Press the mixture firmly into the bottom and slightly up the sides of a 9-inch springform pan. Bake for 10 minutes, then allow to cool while preparing the filling.
2. Make the cheesecake base
   In a large mixing bowl, beat the cream cheese and sugar with an electric mixer on medium speed until completely smooth and creamy, about 3-4 minutes. Add the sour cream and vanilla, and beat until combined. Add eggs one at a time, beating on low speed after each addition just until blended. Do not overmix.
3. Create the chocolate mixture
   Transfer 2 cups of the cheesecake batter to a medium bowl. Add the melted chocolate, cocoa powder, and espresso powder (if using) to this portion. Stir until fully combined and smooth.
4. Create the marble effect
   Pour half of the plain cheesecake batter into the prepared crust. Dollop spoonfuls of the chocolate batter on top. Pour the remaining plain batter over, then dollop the remaining chocolate batter on top. Use a knife or skewer to gently swirl the batters together, creating a marbled pattern. Don't overmix or the distinct colors will blend too much.
5. Prepare water bath and bake
   Wrap the outside of the springform pan with aluminum foil, covering the bottom and extending up the sides. Place the pan in a large roasting pan. Pour hot water into the roasting pan until it reaches about halfway up the sides of the springform pan. Bake for 60-70 minutes, until the edges are set but the center is still slightly jiggly.
6. Cool and chill
   Turn off the oven, crack the door open, and let the cheesecake cool in the oven for 1 hour. Remove from the oven, run a knife around the edges to loosen, and let cool completely at room temperature. Cover and refrigerate for at least 6 hours or overnight before serving.