Fluffy Sponge Chocolate Cake: Light, Airy, and Perfectly Chocolatey

Preheat your oven to 350°F (175°C). Grease and line an 8-inch round cake pan with parchment paper.
Whisk the Eggs and Sugar:

In a large bowl, whisk together the eggs and granulated sugar until the mixture becomes pale and slightly thickened, about 5-7 minutes using an electric mixer on medium speed. This is the key step to getting a light, airy sponge.
Add Wet Ingredients:

Stir in the vanilla extract and warm water or milk, followed by the vegetable oil or melted butter. Mix until smooth.
Sift the Dry Ingredients:

In a separate bowl, sift together the flour, cocoa powder, baking powder, and salt. This will ensure your cake is light and free of lumps.
Combine the Wet and Dry Ingredients:

Gradually fold the dry ingredients into the wet ingredients using a spatula. Be careful not to deflate the batter, as the air bubbles you’ve incorporated into the egg mixture are what make the cake light and fluffy.
Bake the Cake:

Pour the batter into the prepared cake pan and smooth the top.
Bake for 25-30 minutes, or until a toothpick inserted into the center of the cake comes out clean. The cake should be lightly golden on top and spring back when gently touched.
Cool and Serve:

Allow the cake to cool in the pan for 10 minutes before transferring it to a wire rack to cool completely.
Once cool, dust the cake with powdered sugar for an elegant finish, or serve with whipped cream or a layer of your favorite frosting.
Serving and Storage Tips: