Preheat oven to 325°F. Line a 9-inch springform pan with parchment and grease the sides. Mix graham cracker crumbs, brown sugar, salt, and melted butter. Press into bottom of pan and bake for 10 minutes; set aside to cool. Wrap pan in foil to prevent water seepage.

Reduce oven temperature to 300°F. Beat cream cheese, brown sugar, and flour on low until smooth. Add sour cream and vanilla, mix well. Incorporate eggs one at a time. Gently fold in toasted pecans. Pour batter into crust. Place in a water bath and bake for 1 hour 15 minutes until set.

Turn off oven, leave door closed for 30 minutes. Crack oven door and cool another 30 minutes. Remove from oven, refrigerate until fully cooled and firm, about 5-6 hours or overnight.

Make the caramel pecan topping: Heat sugar, butter, and cream until boiling, reach 220°F. Remove from heat, stir in chopped pecans, salt, and vanilla. Cool to room temperature. Spread over cooled cheesecake before serving.