Step 1: Preheat your oven to 325°F (163°C) and grease a 9-inch springform pan. Mix graham cracker crumbs, melted butter, 1 tbsp sugar, and salt. Press firmly into the bottom of the pan and bake for 10 minutes, then let cool.
Step 2: In a large bowl, beat the room-temperature cream cheese and 1 cup sugar on low speed until smooth and creamy. Do not overmix to avoid air bubbles.
Step 3: Add the sour cream and vanilla extract, mixing until just combined. Add eggs one at a time, beating lightly after each addition just until incorporated.
Step 4: Pour the cheesecake batter over the cooled crust. If using a water bath, wrap the pan in foil and place in a larger pan with hot water. Bake for 60-70 minutes until the edges are set but the center still wobbles slightly.
Step 5: Turn off the oven and leave the door slightly ajar for 1 hour to allow the cake to cool slowly. Remove from the oven and cool completely on a wire rack before refrigerating for at least 6 hours or overnight.
Step 6: Once chilled, pour the thick salted caramel sauce over the top of the cake, spreading it to the edges. Sprinkle with sea salt flakes if desired before serving.