01 - Preheat oven to 350°F. Line a 9x9 inch baking pan with parchment paper, allowing overhang for easy removal.
02 - Mix graham cracker crumbs, melted butter, sugar, and salt in a medium bowl until combined. Press firmly into pan bottom. Bake for 10 minutes. Cool slightly.
03 - Beat cream cheese until smooth. Add sour cream and sugar, mix until creamy. Beat in eggs one at a time. Add vanilla and flour, mix until just combined.
04 - Pour filling over crust and smooth top. Bake for 35-40 minutes until center is set but slightly jiggly. Cool completely on wire rack, then refrigerate at least 2 hours.
05 - Heat sugar and water in saucepan over medium heat, swirling until mixture turns deep amber. Remove from heat, whisk in butter. Slowly add heavy cream while whisking until smooth. Stir in salt.
06 - Cool caramel slightly, then pour over chilled cheesecake. Spread evenly and refrigerate for 1 hour. Lift bars from pan using parchment, cut into 16 squares.