- Crust:
- 1 cup crushed vanilla wafers
- 2 tablespoons butter, melted
- 1 tablespoon white sugar
- 1 tablespoon unsweetened cocoa powder
- Filling:
- 1 tablespoon instant coffee powder
- 2 tablespoons coffee-flavored liqueur (such as Kahlua®)
- 4 (1 ounce) squares semisweet chocolate, grated
- 2 pounds cream cheese, room temperature
- 1 cup white sugar
- 4 eggs, room temperature
- Topping:
- 1 cup sour cream
- 2 tablespoons white sugar
- 1 teaspoon coffee-flavored liqueur (such as Kahlua®)
- 1 teaspoon unsweetened cocoa powder
- To make the crust, combine vanilla wafer crumbs, 2 tablespoons melted butter, 1 tablespoon sugar, and 1 tablespoon cocoa; toss with a fork to mix. Press into bottom of a 9-inch springform pan. Wrap the pan bottom in aluminum foil. Refrigerate while preparing the filling.
- Preheat oven to 350 degrees F (175 degrees C). Bring a kettle of water to a boil.
- Grate or finely chop the semisweet chocolate and put it into the top of a double boiler. Place over hot water. When almost melted, remove from heat and stir until completely melted. (Chocolate can also be melted in a microwave in 30-second increments, stirring frequently.) Set aside.
- Combine cream cheese and 1 cup sugar; mix with an electric mixer until well blended.
- Dissolve coffee powder in 2 tablespoons coffee liqueur. Add the coffee mixture and the cooled melted chocolate to the cream cheese batter; mix until combined.
- Add the eggs one at a time, mixing just until incorporated. Pour the filling into the prepared crust; tap the pan on the countertop to smooth the surface and settle the batter.
- Place springform pan in a large baking dish. Place baking dish on oven rack; carefully pour boiling water into the baking pan until it comes halfway up the sides of the cheesecake pan.
- Bake in a preheated oven for 1 hour.
- Remove the pan from the oven, and remove the springform pan from the water bath; discard any remaining water.
- For the topping, stir together the sour cream, 2 tablespoons sugar, 1 teaspoon coffee liqueur and 1 teaspoon of cocoa. Spread over the top of the hot cheesecake. Return cheesecake to the oven for 5 minutes. Remove from oven and allow to cool to room temperature.
- Refrigerate at least 4 hours or overnight before serving.