1: Preheat the oven to 325F.
2: In a bowl, mix egg yolks, 50g sugar, vanilla extract, baking powder, cake flour, and a pinch of salt.
3: Add milk and vegetable oil to the mixture and combine well.
4: In another bowl, prepare the meringue by whipping the egg whites and 70g sugar until stiff peaks form.
5: Fold the meringue into the egg yolk mixture gently.
6: Add orange zest and incorporate it into the batter.
7: Pour the batter into a 9x13 pan.
8: Bake for 30 minutes.
