In a bowl, mix lemon juice, lemon zest, and vegetable oil.
Beat egg whites until foamy, gradually adding sugar. Then fold in egg yolks.
In a separate bowl, sift flour and baking powder together, then gently fold into the egg mixture.
Add the lemon-juice mixture and mix until combined.
Pour batter into a 20 cm round cake mold and bake at 160°C (320°F) for 35 minutes. Let cool.
2. Make the Lemon Filling:
In a saucepan, combine eggs, lemon juice, lemon zest, sugar, and cornstarch.
Cook over medium heat, stirring constantly, until thickened.
Strain the mixture and cover with plastic wrap to cool.
3. Make the Cream Cheese Filling:
Whip cream with powdered sugar until soft peaks form.
Fold in cream cheese and vanilla extract until smooth.
4. Prepare the Syrup:
Mix water, sugar, and lemon juice in a small saucepan until sugar dissolves. Set aside.
5. Assemble the Cake:
Slice the cake into 3 equal layers.
Moisten each layer with lemon syrup.
Layer the cake with lemon filling and cream cheese filling alternately.
Cover the entire cake with cream cheese frosting.
Chill in the refrigerator for at least 6 hours before serving.
