Method
Place a rack in the middle of the oven and preheat the oven to 180°C. Grease the bottom and sides of an 8×3 inch round cake pan with butter.
Cut a sheet of parchment paper into four strips: two 16 1/2 x 2 inch strips and two 16 1/2 x 4 inch strips.
Grease and cut two 2-inch strips, greased side down, in the center of the pan, creating an “X” at the bottom of the pan. Press them around the edges and up (this creates a scarf that will help you release the cake from the pan after baking).
Line the bottom of the pan with a round piece of baking paper (20 cm). Grease one side of each 4-inch strip of parchment paper and wrap it around the inside walls of the pan so that the greased sides touch the sides of the pan. They overlap each other to form a rim that is higher than the edge of the cake pan. Set aside while you prepare the cheesecake.
Put a kettle or pot of water to boil. You will use it as a water bath later.
Separate the eggs. Place the egg whites in the bowl of a food processor. Place the egg yolks in a small bowl.
Place a large pot with 1 inch of water on the bottom, place over medium heat, and bring to a boil. In a large heatproof bowl (that fits snugly over the pan), add butter, cream cheese, heavy cream, sour cream, 1/2 cup sugar, and salt. Place the bowl over the boiling water.
Mix with a whisk until the cream cheese melts and the mixture is smooth. Remove from heat.
Mix together the lemon juice and vanilla extract, then gradually add the egg yolks.
Dust the dough with cake flour and mix. Do not exaggerate.
In the bowl of a stand mixer fitted with the whisk attachment, beat the egg whites on medium speed until light and fluffy. Gradually add 1/3 cup sugar, a tablespoon at a time, beating on medium speed until stiff peaks form. When you remove the whisk, the top stays straight, but the tip folds back.
Do not beat the meringue too hard, otherwise it will become crumbly.
Using a whisk, gently stir 1/3 of the meringue into the cheese mixture until there are no streaks left. Be careful not to squeeze the air out of the egg whites. Repeat the process, adding the meringue a third at a time. Pour the batter into the prepared cake pan.