Combine egg yolks, yogurt, salt, and lemon zest together and whisk well. Sift all-purpose flour and corn starch into the egg yolk mixture and continue whisking until there are no more lumps. Set aside.
Pour batter into a 6-inch round springform pan lined with parchment paper. Tap the pan a few times down on the table to remove any air bubbles trapped in the batter.
Light, airy, fluffy with a light lemon flavor. This ultimate yogurt cake is also moist and jiggly; just the perfect texture! It's lower in calories so everyone can enjoy a slice.