Prepare the Cake Pan and Oven

1. Preheat the Oven: Preheat your oven to 350°F (175°C). Grease an 8-inch round cake pan, line the bottom with parchment paper, and lightly grease the paper.
2. Sift the Dry Ingredients: In a mixing bowl, sift together the all-purpose flour and cornstarch. Set aside.

Whisk the Eggs and Sugar

3. Prepare the Egg Mixture: In a large bowl or the bowl of a stand mixer, combine the eggs and granulated sugar.
4. Whisk Until Pale and Thick: Using a hand mixer or stand mixer on high speed, beat the eggs and sugar for 8-10 minutes, or until the mixture is pale, tripled in volume, and leaves a thick ribbon when the whisk is lifted.

Fold in the Dry Ingredients and Butter

5. Gently Fold in the Flour: Using a spatula, gently fold the sifted flour and cornstarch mixture into the egg mixture, a little at a time. Be careful not to overmix, as this will deflate the batter.
6. Add the Melted Butter: Pour the melted and cooled butter down the side of the bowl, and gently fold it into the batter until just combined. This step requires a light hand to avoid deflating the batter.

Bake the Cake

7. Transfer to the Pan: Pour the batter into the prepared cake pan, smoothing the top with a spatula.
8. Bake the Cake: Place the pan in the preheated oven and bake for 20-25 minutes, or until the cake is golden and springs back when lightly pressed in the center. A toothpick inserted into the center should come out clean.
9. Cool the Cake: Remove the cake from the oven and let it cool in the pan for 5 minutes. Then, run a knife around the edges, turn it out onto a wire rack, and peel off the parchment paper. Allow the cake to cool completely.

Serve or Decorate the Cake

10. Serve or Decorate: The Genoise cake is now ready to be enjoyed on its own, dusted with powdered sugar, or layered with fillings like whipped cream, fruit, or chocolate ganache. Slice horizontally for layers, if desired.