Step 1: Prepare the Crust

1. Preheat your oven to 325°F (163°C).
2. In a mixing bowl, combine chocolate cookie crumbs, melted butter, and sugar.
3. Press the mixture into the bottom of a 9-inch springform pan.
4. Bake for 10 minutes, then set aside to cool.

Step 2: Make the Strawberry Swirl

1. In a small saucepan, combine strawberries, sugar, cornstarch, and water over medium heat.
2. Simmer for 5 minutes, stirring occasionally, until the strawberries break down and the sauce thickens.
3. Blend the mixture with an immersion blender or food processor until smooth.
4. Strain through a fine mesh sieve to remove seeds. Set aside to cool.

Step 3: Prepare the Chocolate Cheesecake Filling

1. In a large bowl, beat cream cheese and sugar until smooth and fluffy.
2. Add eggs, one at a time, mixing on low speed after each addition.
3. Mix in sour cream and vanilla extract until well combined.
4. Pour in melted chocolate and mix until smooth.

Step 4: Assemble the Cheesecake

1. Pour the chocolate cheesecake batter over the cooled crust.
2. Drizzle spoonfuls of strawberry puree over the top.
3. Use a toothpick or skewer to gently swirl the strawberry sauce into the batter.

Step 5: Bake the Cheesecake

1. Bake at 325°F (163°C) for 50-55 minutes, or until the edges are set but the center is slightly jiggly.
2. Turn off the oven and crack the door slightly. Let the cheesecake cool inside for 30 minutes.
3. Transfer to a wire rack and cool to room temperature.
4. Refrigerate for at least 4 hours (preferably overnight) before serving.