JAPANESE FLUFFY CHEESECAKE (CHIIZUKEIKI)

1. Place a rack in the middle position in the oven and preheat the oven to 320 degrees Fahrenheit
2. Lightly grease the sides and bottom of a 9-inch spring form cake pan with the oil and line it with baking parchment
3. Wrap the outside of the pan in foil to prevent leakage and set aside
4. In a small bowl, whisk together the egg yolk and milk. Set Aside

5. Put the cream cheese, ¼ cup of the sugar, and the salt in a large bowl, using an electric mixer at medium-high speed, blend them together until smooth and soft. Turn and speed down to medium and slowly pour the egg yolk mixture into the bowl. When the mixture is silky, add the butter and combine. Reduce the speed to slow and add the flour mixture all at once. Mix gently but thoroughly and set aside
6. Put a kettle or pot of water over high heat, cover, and bring to a boil. Reduce the heat to medium low, just to keep the water hot
7. In a clean, medium bowl, beat the egg whites at medium-low speed until they’re white and foamy. Continue beating, adding the remaining ¼ cup of sugar, 1 tablespoon at a time. When all of the sugar has been added, turn the mixer speed up to high and whip the egg whites to thick, lustrous, stiff peaks, Don’t over whip, or the whites will become dry and clumpy.
8. Scoop ⅓ of the egg whites into the cream cheese mixture and fold to combine. Add the rest of the whites and use a spatula to fold them in gently. Be careful not to squash the air out of the whites
9. Pour the batter into the cake pan. Lift the pan 2-3 inches above a flat surface and drop it to release any bubbles, then drop the pan once more to level out the top of the batter.
10. Put the cake pan in a large, deep roasting pan. Pull the oven rack part way out and place the pan on it. Making sure not to spill any water into the cake pan, pour the hot water into the roasting pan until it reaches halfway up the sides of the cake pan. Carefully slide the oven rack back into the oven
11. Bake until the top is lightly browned, about 1 hour. Check for doneness by inserting a toothpick into the middle. If it comes out clean, the chiizukeiki is fully baked. If necessary, continue baking, checking every 10 minutes
12. When the cake is done, turn off the oven and open the door a few inches. Leave the cake in the oven to cool slowly for 15 minutes
13. Take the roasting pan out of the oven and transfer the cake pan to a wire cooling rack. Allow the chiizukeiki to cool completely, about 1 hour. Pop open the spring form pan and slide the cake onto a plate. Peel the parchment off the sides of the cake, chill in the refrigerator for 2 to 3 hours, and serve cold
14. To store the chiizukeiki, refrigerate or freeze it in a tightly sealed container. It will keep for 3 days in the refrigerator or 1 month in the freezer