Preheat oven to 350°F (175°C). Wrap the outside of a 9-inch springform pan with 3 large sheets of heavy-duty aluminum foil. Spray the inside bottom with non-stick spray and line with a round of parchment paper.
Crush Oreos in a food processor until fine crumbs form. Mix with melted butter until moistened. Press firmly into the bottom and 1 inch up the sides of the prepared pan. Bake for 10 minutes, then set aside to cool. Reduce oven temperature to 325°F (163°C).
In a small bowl, combine caramel sauce with flour or cornstarch until smooth. Stir in chopped pecans. Spread evenly over the cooled crust and refrigerate while preparing the filling.
Beat softened cream cheese in a stand mixer on medium speed for 3 minutes until smooth. Scrape down the bowl. Gradually add sugar and beat for 2 more minutes. Add vanilla and salt, then mix briefly.
Reduce mixer to low speed. Add eggs one at a time, beating just until each disappears. Do not overmix. Pour in heavy cream and mix just until combined, about 20-30 seconds.
Pour the cheesecake batter slowly over the chilled caramel pecan layer. Smooth the top with an offset spatula. Place the foil-wrapped pan in a roasting pan and pour hot water into the roasting pan to reach 1 inch up the sides.
Bake at 325°F (163°C) for 55-65 minutes until edges are set and the center 2-3 inches jiggles gently. Turn off the oven and leave the cheesecake inside with the door closed for 1 hour, then crack the door open for 30 minutes.
Remove from water bath and peel away foil. Run a thin knife around the edge to loosen the cheesecake. Cool completely on a wire rack for 2-3 hours. Cover and refrigerate for at least 6 hours, preferably overnight.
Place chocolate chips in a heat-safe bowl. Heat heavy cream in a small saucepan until simmering at the edges. Pour hot cream over chocolate, let sit 2 minutes, then whisk until smooth. Allow to cool for 10-15 minutes until thickened but still pourable.
Release and remove the springform ring. Pour the ganache over the cheesecake and spread evenly. Drizzle with additional caramel sauce and sprinkle with toasted pecans. Refrigerate for 20-30 minutes to set before serving.