Chocolate Sponge Cake – Light & Classic.

A classic chocolate sponge cake (often referred to as a Genoise in French pastry) is the polar opposite of a dense mud cake. It does not rely on heavy fats or chemical leaveners like baking powder; instead, it uses the physical aeration of eggs to create a structure that is as light as air.

The Anatomy of the Rise

In a classic sponge, the “lift” comes from the millions of tiny air bubbles trapped during the egg-whisking process.

Feature	Regular Butter Cake	Classic Sponge Cake
Leavening	Baking Powder/Soda	Aerated Eggs
Primary Fat	Creamed Butter	Minimal (Melted Butter)
Texture	Dense, moist, crumbly	Springy, light, flexible
Best Use	Heavy Frostings	Syrups, Creams, and Fruit

Ingredients

4 Large Eggs: Room temperature (essential for volume).¹
2/3 cup (130g) Granulated Sugar.
2/3 cup (85g) All-Purpose Flour.
1/4 cup (25g) Dutch-Processed Cocoa Powder: High quality is key here.
2 tbsp (30g) Unsalted Butter: Melted and cooled.
1 tsp Vanilla Extract.
Pinch of Salt.

Instructions

1. The Warm Whisk

Preheat your oven to 350°F (175°C).² Grease an 8-inch round cake pan and line the bottom with parchment paper.

The Pro Tip: For maximum volume, place your eggs and sugar in a heatproof bowl over a pot of simmering water. Whisk constantly until the mixture is lukewarm to the touch ($110^\circ\text{F}$ or $43^\circ\text{C}$), then move to your stand mixer. Warm eggs hold air much better than cold ones.

2. The Ribbon Stage

Beat the eggs and sugar on high speed for 8–10 minutes. You are looking for the “ribbon stage”: when you lift the whisk, the batter should fall back into the bowl in a thick trail that stays visible on the surface for at least 3 seconds.³

3. The Sift & Fold

Sift the flour, cocoa, and salt together twice.

The Gentle Hand: Sift the dry ingredients over the egg mixture in three batches. Use a large metal spoon or spatula to fold them in using a “figure-eight” motion.
The Goal: Be extremely gentle. If you stir vigorously, you will pop the air bubbles and end up with a flat, rubbery disc.

4. The Fat Integration

Take a small scoop of your batter and stir it into the melted butter and vanilla in a separate small bowl. Once combined, fold this “lightened butter” back into the main batter. This prevents the heavy butter from sinking to the bottom of the pan.

5. The Bake

Pour the batter into the prepared pan. Bake for 25–30 minutes.

The Touch Test: The cake is done when the sides slightly pull away from the pan and the top springs back instantly when lightly pressed.

6. The Cooling

Let the cake cool in the pan for 5 minutes, then invert onto a wire rack. Remove the parchment paper immediately to prevent the cake from “sweating” and becoming soggy.

Culinary Success Tips

Cocoa Sifting: Cocoa powder is notoriously lumpy.⁴ Sifting it with the flour is mandatory to avoid “cocoa pockets” in your finished sponge.
Avoid Greasing the Sides: Some pastry chefs prefer not to grease the sides of the pan, only the bottom. This allows the sponge to “climb” the walls of the pan, resulting in a taller, more even rise.
The Soak: Classic sponges are naturally a bit drier than butter cakes. It is traditional to brush the layers with a simple syrup (sugar and water) or a liqueur before filling with cream to add moisture.

FAQ

Can I make this gluten-free?

Yes. Use a high-quality 1:1 gluten-free flour blend. However, avoid using nut flours (like almond flour) as a direct swap, as the weight of the oils in nuts will deflate the egg foam.

Why did my cake sink in the middle?

This usually happens if the oven door was opened too early or if the eggs weren’t whisked to a stable enough ribbon stage.

Can I use this for a Swiss Roll?

Absolutely! This batter is flexible enough to be baked in a flat sheet pan (jelly roll pan) for 10–12 minutes and rolled while warm.

Would you like me to find a recipe for a “Whipped Dark Chocolate Ganache” to fill and frost this sponge cake?