Preheat your oven to 325°F (160°C). In a mixing bowl, combine graham cracker crumbs, sugar, and melted butter until crumbly. Press this mixture firmly into the bottom of a 9-inch springform pan to create a solid crust. Bake for 10 minutes until slightly golden, then remove from the oven and allow it to cool while you prepare the cheesecake layer.

In a stand mixer, beat room-temperature cream cheese on medium speed for 3-4 minutes until completely smooth and fluffy. Gradually add in granulated sugar, mixing well, then incorporate eggs one at a time, mixing minimally after each addition to avoid over-beating. Lastly, mix in vanilla extract and sour cream until fully combined, then pour this creamy mixture over the cooled crust.

Wrap the bottom of the springform pan securely in aluminum foil to prevent water from seeping in. Place it inside a large roasting pan, then pour hot water into the roasting pan, filling it halfway up the sides of the springform pan. Bake in the preheated oven for 45-55 minutes, or until the cheesecake layer is set but still slightly jiggly in the center.

After baking, remove the cheesecake from the oven and let it cool on the counter for an hour. Then, refrigerate the cheesecake for at least 4 hours or, for the best results, overnight.

In a saucepan, heat heavy cream over medium heat until it just begins to simmer, then remove it from the heat. Whisk together egg yolks, sugar, vanilla, and salt in a separate bowl. Gradually ladle the hot cream into the egg mixture while whisking vigorously to temper the yolks, then return the entire mixture to the saucepan and cook over low heat until thickened slightly.

Once the custard has cooled, carefully pour it over the chilled cheesecake, spreading it evenly. Return the entire pan to the refrigerator for an additional 2-3 hours, allowing the custard layer to set completely before serving.

When you’re ready to serve, sprinkle an even layer of granulated sugar over the cooled custard. Use a kitchen torch to caramelize the sugar, moving the flame in a circular motion until it melts and turns a rich amber color.