Preheat the oven to 350 degrees F and prepare a 9x13 inch baking dish by spraying it with nonstick cooking spray.

Using a food processor, combine graham crackers, pecan halves, and brown sugar. Pulse until finely ground. Add melted butter and pulse until well combined. Press the mixture evenly into the bottom of the prepared baking dish. Bake the crust for 10 minutes.

Clean the food processor bowl thoroughly. Add softened cream cheese, sour cream, sugar, eggs, flour, vanilla extract, and salt. Process until very smooth, ensuring no lumps remain.

Pour the cheesecake batter over the pre-baked crust, smoothing evenly. Tap the dish gently on the countertop to release air bubbles. Bake for 30-40 minutes, or until a toothpick inserted in the center comes out clean.

While the cheesecake bakes, combine chopped pecans, brown sugar, heavy cream, butter, cinnamon, and salt in a small saucepan over medium heat. Bring to a boil, then reduce heat and simmer while stirring continuously for 2-3 minutes. Remove from heat.

Once the cheesecake finishes baking, remove from the oven. Pour the warm pecan pie topping evenly over the cheesecake layer, spreading with a spatula. Chill the cheesecake for at least 2 hours to set before serving.

Use a serrated knife to cut the cheesecake into bars. For clean slices, wipe the knife with a wet paper towel between cuts.