Directions:
Preheat your oven to 350 degrees F and lightly grease an 8-inch cake pan. Consider lining it with parchment paper for easy removal.
Sift together flour, baking powder, and salt in a medium bowl.
In a large bowl, beat sugar, butter, and oil until light and fluffy. Add egg yolks one at a time, then stir in vanilla extract and lemon zest.
Gradually add dry ingredients to the sugar mixture, alternating with lemon juice and milk. Stir until the batter is smooth.
In a separate bowl, whip egg whites until stiff peaks form. Gently fold them into the batter.
Pour the batter into the prepared cake pan, smoothing the top with a spoon or spatula.
Bake for 40 to 45 minutes or until a toothpick inserted in the center comes out clean.
Allow the cake to cool in the pan before removing. Let it cool completely for optimal results.
Dust the cake with powdered sugar before serving for an elegant touch.