Preheat the oven to 350°F and have ready a 9" springform sprayed with nonstick cooking spray. Add a round of parchment paper to the bottom of the pan, if desired. Cut 2 large pieces of foil and lay them down in a cross shape on a work surface. Then, wrap the foil up the sides of the pan.

In a large bowl, combine the graham cracker crumbs, melted butter, sugar, and salt and stir until evenly moistened. Transfer the mix to the prepared pan and using a flat-bottomed measuring cup, press down to form the crust.

Bake on the center rack for 10 minutes. Then, remove from the oven and allow to cool completely.

Reduce the oven temperature to 250°F and once the crust has cooled, it's almost time to make the cheesecake filling. Also, have ready about 3 cups of boiling hot water and a roasting pan or casserole dish large enough to fit the springform pan inside.

Add the cream cheese and granulated sugar to the bowl of a stand mixer fitted with a paddle attachment. If you do not have a stand mixer, use a large mixing bowl and a handheld mixer. Mix on medium-low speed for 2-3 minutes.

Scrape down the sides of the bowl and mix once more. Add the sour cream and mix just to combine.

In a small separate bowl, whisk the eggs and the egg yolk together and add to the cream cheese mixture along with the vanilla extract and salt. Mix to combine, then scrape down the sides of the bowl, and mix once more. Do not overmix the filling.

Pour the contents of the bowl over the crust and set the springform pan inside of the roasting pan. Add hot water to the roasting pan (taking care not to splash into any onto the cheesecake) -- you only need about an inch of water. Transfer to the center rack of the oven to bake.

Bake for about 1 hour and 20 minutes; the cheesecake is done when the sides are set, but the center still jiggles (like Jell-O) when gently nudged.

Remove the cheesecake from the oven, transfer to a cooling rack, and run a sharp knife along the edges. Once the sides of the pan are cool to the touch, remove the foil from the sides of the pan, cover the cheesecake with plastic wrap or aluminum foil and transfer it to the refrigerator to cool completely, at least 4 hours or up to 3 days.

Remove the cheesecake from the refrigerator about 30 minutes prior to serving. Remove the band from the pan. Serve directly from the pan, or use a sharp knife or large metal spatula to gently unstick the crust from the pan. Then, using two large offset spatulas, transfer it to a serving dish.

Once the cheesecake is chilled and out of the pan, add the sour cream topping. To make it, combine the sour cream and powdered sugar in a small bowl and stir to combine. Then, pour it over the top of the cheesecake and spread to the edges using an offset spatula.