Instructions

• Make the caramel sauce: In a large pot over medium heat, add 1 cup (200 g) granulated sugar and heat, stirring occasionally, until the sugar is completely melted and turns a light amber color.
• Reduce heat to low and carefully pour in ½ cup (120 ml) heavy cream (the sugar will bubble). Stir until smooth.
• Add the ??cup (75 g) unsalted butter (cut into pieces) and stir until fully melted and the sauce is smooth. Remove from heat, stir in 1 teaspoon (5 ml) vanilla extract and ¼ teaspoon salt. Transfer the caramel to a heatproof bowl or jar and let cool at least 30 minutes before using.
• Preheat oven to 350°F (180°C) [160°C fan]. Lightly grease a 9-inch (23 cm) springform pan if desired.
• Make the crust: Place 24 regular whole Oreo cookies (one 9.5 oz / 270 g package) in a food processor and pulse until fine crumbs form. Add ¼ cup (56 g) melted unsalted butter and pulse until the mixture resembles wet sand.
• Press the crumb mixture firmly into the bottom of the springform pan and slightly up the sides using the bottom of a measuring cup or a glass.
• Wrap the bottom and sides of the prepared springform pan with two large pieces of aluminum foil so the seams of the pan are covered (this prevents water from entering during the water bath).
• Bake the crust in the preheated 350°F (180°C) oven for 10 minutes. Remove from oven and cool on a wire rack for 15 minutes.
• Lower the oven temperature to 325°F (160°C) [140°C fan].
• Make the cheesecake batter: In a large bowl, beat 32 ounces (900 g) cream cheese (softened to room temperature) with 1 cup (200 g) granulated sugar and 2 tablespoons (15 g) all-purpose flour until smooth and no lumps remain.
• Add 4 large eggs, one at a time, beating and scraping down the sides of the bowl between each addition. Add ½ cup (125 g) sour cream and 1 teaspoon (5 ml) vanilla extract and mix until combined.
• Divide the batter evenly into two bowls. To one bowl add the ??cup (80 ml) caramel sauce you made in step 3 and mix until smooth. To the other bowl add 4 ounces (113 g) melted and cooled semi-sweet chocolate (or ½ cup chocolate chips melted and cooled) and mix until smooth.
• Assemble the cheesecake: Sprinkle the crust with half of the ¼ cup finely chopped pecans called for in the ingredients. Spread half of the caramel-flavored batter over the crust. Dollop half of the chocolate batter over the caramel in 5–6 spots and use a butterknife to swirl the chocolate into the caramel.
• Sprinkle the crust with the remaining chopped pecans (the rest of that ¼ cup). Spread the remaining caramel batter over the crust, then dollop the remaining chocolate batter in 5–6 spots and swirl again with a butterknife.
• Place the foil-wrapped springform pan into a roasting pan. Pour hot (not boiling) water into the roasting pan to come 1–2 inches up the sides of the springform pan to create a water bath.
• Carefully transfer the roasting pan to the preheated 325°F (160°C) oven and bake for 50–60 minutes, or until the cheesecake edges are set and the center still wobbles slightly when the pan is gently shaken.
• Turn the oven off and open the oven door. Let the cheesecake cool in the oven for 1 hour. After 1 hour, remove the cheesecake from the oven and let it cool uncovered on a wire rack until completely cool, about 1 more hour.
• Refrigerate the cooled cheesecake, covered, for at least 6 hours or overnight.
• Before removing the springform ring, run a butter knife around the edge of the cheesecake to loosen it, then remove the sides of the pan.
• Make the chocolate ganache: Place 3 ounces (85 g) semi-sweet chocolate (or ½ cup chocolate chips) in a medium bowl. Heat ¼ cup (60 ml) heavy cream until steaming (not boiling), pour it over the chocolate, let sit 1 minute, then stir until smooth. Spread the ganache evenly over the chilled cheesecake.
• Make the whipped cream: In a large bowl, combine 1 cup (240 ml) very cold heavy whipping cream, ½ cup powdered sugar, and 1 teaspoon (5 ml) vanilla extract. Whisk on high speed until stiff peaks form.
• Pipe or dollop the whipped cream around the outside edge of the cheesecake.
• Drizzle the top of the cheesecake with ¼ cup (60 ml) of the reserved caramel sauce from step 3.
• Sprinkle the top with the remaining ¼ cup finely chopped pecans. Chill briefly if needed to set decorations, then serve.