Remove the refrigerated ingredients from the fridge at least 2 hours before you start mixing. They must be at room temperature.
Preheat your oven to 300 degrees F. Boil a kettle of water, let the water slightly cool, then carefully pour them into a 9 X 13-inch pan. Place the pan with the water on the lowest oven rack.
Generously butter the sides and bottom of a 9-inch springform pan. Line the bottom with a circle of parchment paper, and butter the parchment too.
Mix the batter
Place the cream cheese in a large bowl. Using a handheld mixer set to the lowest speed, lightly beat the cream cheese until smooth.
Add the sour cream (if it's at room temperature, there will be some liquid separation - add the liquid too), the vanilla, and stevia. Mix just until incorporated. Don't over mix.
Add the eggs one by one, beating after each addition. Only beat for as long as it takes to get a smooth batter, then stop. Don't over mix.
Pour the batter into the prepared pan. Smooth the top out with a spatula.
Bake the cake
Place the pan in the oven, on the middle rack, above the water pan. Bake, without opening the oven door, until the edges are very light brown and slightly puffed, and the center is still sunken but not liquid, 50-60 minutes. If you shake the pan gently, the center will jiggle at this point.
Cool the cake
Turn the oven off, and leave the cake in the oven, with the oven door ajar, for one hour. Then remove the cake from the oven and place the pan on a cooling rack. If the cake's edges haven't pulled away from the pan, gently run a knife around the rim of the pan to loosen the cake's edges from the pan. This helps prevent cracks from forming as the cake cools. Let the cake cool completely in the pan on the counter, about 2 more hours.
When the cake is completely cool, transfer it, still in the pan, to the fridge. Refrigerate the cake, uncovered (to prevent condensation), for at least 8 hours, and preferably for 24 hours, before slicing and serving.
Serve the cake
Remove the cheesecake from the fridge 30 minutes before you plan to serve it and remove the springform pan's outer rim. Use a very sharp, non-serrated knife for cutting the cake. To prevent messy slices, dip your knife in hot water and wipe it clean before each cut.
Place leftover slices in sealed containers in the fridge for up to 5 days. Remove them from the fridge 30 minutes before serving.
What to do if your cake does crack? The next day, after it's been refrigerated, dip a dinner knife in warm water. Gently and repeatedly press near the crack until it closes. Then use the knife, again dipped in warm water, to smooth the top of the cake out. Here's a good guide to fixing a cracked cheesecake.Or simply top the cake! Toppings were pretty much invented for the purpose of hiding these very common cracks, so that's an option too - blueberry compote and strawberry compote are two excellent options. Just make sure to top the cake right before you serve it.