Preheat your oven to 320°F (160°C). Line a 6-inch pan with parchment paper.
Using a beater, whisk the eggs and granulated sugar together until they become pale and fluffy.
Sift the cake flour (or all-purpose flour) into the egg-sugar mixture. Gently fold the flour into the mixture using a spatula. Avoid overmixing to retain the cake's fluffiness.
Pour the batter into the prepared pan and spread it evenly. Place it in the preheated oven and bake for 20-25 minutes, or until a toothpick inserted into the center comes out clean.
Once baked, let the cake cool in the pan for a few minutes. Then transfer it to a wire rack to cool completely.