In a large mixing bowl, combine the egg yolks and sugar. Beat with a mixer until the mixture is light and fluffy.
Add the cornstarch, Greek yogurt, and vanilla extract to the yolk mixture. Mix everything together until well combined and set aside.
Add a pinch of salt to the egg whites. Beat with a mixer until the whites reach stable peaks, forming a meringue.
Gently fold the meringue into the yogurt mixture, taking care not to deflate the egg whites.
Pour the combined mixture into a greased baking pan. Bake in a preheated oven at 170°C (338°F) for 50 minutes or until the cake is set and lightly golden on top.
Once cooled, sprinkle the top of the cake with powdered sugar for a sweet, decorative touch.
