A light and cotton soft cheesecake that is appropriately indulgent without being too rich.
Preheat oven to 350 F. Grease and line an 8-inch springform pan with parchment paper. Combine egg yolks, 1 egg and condensed milk in a bowl and stir together until smooth.
Bring about 2-3 inches of water in a pot to simmer. Place a heat-safe glass bowl over the pot (it should fit snugly). Add cream cheese and oil to the bowl. Once the cream cheese is soft, stir the mixture until it is smooth. Let this mixture cool slightly. Add the egg mixture to the cream cheese mixture and stir well. Add the flour and stir the mixture until smooth.
In a bowl of a stand mixer, beat the egg whites until frothy. Add the lemon juice and continue beating until soft peaks form. Gradually add the sugar until egg whites reach the stiff peaks stage.
Fold 1/3 of the egg whites to the yolk batter and stir until combined. Gently fold the remaining egg whites until mixture is uniform in color. Pour batter into the prepared baking pan. Lightly tap it against the counter to release air pockets. Bake at 350 F in a water bath for 30 minutes. Lower temperature to 265 F and bake for 1 hour. Once the top turns golden, cover it with foil to avoid over browning. Let the cake cool for 5 minutes or so. Transfer it to a serving plate and sprinkle powdered sugar on top.
To make a water bath set up for baking, fill a large rimmed baking pan with about one and a half to two inches water. Position the cake pan ( filled with the cake batter) in the center.