Preheat oven to 350°F. Spray a 9x13 inch baking dish with nonstick cooking spray.
For the crust: In a food processor, pulse graham crackers, pecans, and brown sugar until fine crumbs form. Add melted butter and pulse until combined. Press firmly into prepared baking dish. Bake for 10 minutes, then cool.
For the cheesecake: Clean food processor. Add cream cheese, sour cream, sugar, eggs, flour, vanilla, and salt. Process until smooth. Pour over cooled crust and tap to remove air bubbles.
Bake for 30-40 minutes until center still jiggles slightly. Cool completely.
For the topping: In a saucepan, combine pecans, brown sugar, heavy cream, butter, cinnamon, and salt. Bring to boil, then simmer 2-3 minutes until thickened.
Pour warm topping over cooled cheesecake. Spread evenly. Refrigerate at least 2 hours before cutting. Use serrated knife for clean slices.