This light and airy chocolate sponge cake has been my signature celebration treat for years. I first developed this version on a rainy afternoon when I wanted a chocolate cake that felt delicate — not dense — and could hold a bright jam filling without collapsing. The texture is what sets it apart: an ethereal crumb with soft springs when you touch the top, and a faint chocolate aroma that never overwhelms the palate. I discovered early that separating eggs, gentle folding, and a simple syrup soak were the keys to keeping the layers tender and evenly moist.

I often bake this for birthdays and small dinner parties because it travels well and looks stunning assembled. Paired with homemade raspberry jam and a lightly sweetened chocolate whipped cream, it becomes surprisingly elegant — light enough for a second slice, rich enough to feel indulgent. There’s a particular memory of handing a slice to my grandmother, who closed her eyes and said it reminded her of a bakery cake she’d loved decades ago; that moment confirmed the recipe was worth keeping. If you’re looking for a crowd-pleasing, delicate chocolate layer that’s forgiving yet technical enough to teach good technique, this one’s for you.

Ingredients

• All-purpose flour: 2 tablespoons — use a reliable brand like King Arthur for consistent protein; contributes structure without weighing the crumb.
• Cornstarch: 1/3 cup — helps mimic cake flour by lowering gluten development and keeping the crumb soft and tender.
• Unsweetened cocoa powder: 2 tablespoons for the sponge and 3 tablespoons for the whipped cream — choose Dutch-processed for a deeper, smoother chocolate note.
• Instant coffee powder: 1 teaspoon — just enough to intensify chocolate flavor without making the cake taste like coffee.
• Baking powder & salt: 1/4 teaspoon baking powder and 1/4 teaspoon salt — small amounts for balanced lift and seasoning.
• Large eggs: 4, separated, at room temperature — eggs are the primary leavening here; room temperature eggs whip more voluminously.
• Granulated sugar: 2/3 cup total (split into 1/3 cup for whites and 1/3 cup for yolks) — splitting helps stabilize whipped whites and sweeten yolk ribbons for structure.
• Neutral oil (canola): 2 tablespoons — adds moisture without solid fats that would weigh down the batters.
• Warm water: 1 1/2 tablespoons — hydrates sugar and aids emulsification in the yolk mixture.
• Vanilla extract & white vinegar: 2 teaspoons vanilla and 1/8 teaspoon vinegar — vanilla for aroma; vinegar gives extra stability to whipped whites.
• Simple syrup: 1/4 cup sugar mixed with 1/4 cup boiling water — a light soak keeps these lean sponges tender.
• Whipping cream: 2 cups cold heavy cream, 3 tablespoons powdered sugar, and 3 tablespoons unsweetened cocoa — whipped to stiff peaks for the icing.
• Raspberry jam: about 1 batch of a good thick jam — preserves add acidity and bright fruit notes that lift the chocolate.
• Fresh strawberries: one small punnet for decorating — halved or quartered, they give texture and color.

Instructions

Preheat & prepare pans: Preheat your oven to 320°F with the fan on. If using a conventional oven, set to 347°F. Line the bottoms of two 8 x 3-inch cake pans with baking paper but leave the sides ungreased — the batter needs friction to climb and retain height. Combine dry ingredients: Whisk together 2 tablespoons all-purpose flour, 1/3 cup cornstarch, 1/4 tsp baking powder, 2 tbsp cocoa, 1 tsp instant coffee, and 1/4 tsp salt until homogeneous. No need to sift now; set aside. Whip egg whites: In a clean bowl with a whisk attachment or hand mixer, whip 4 egg whites with 1/8 teaspoon white vinegar. After 30 seconds at medium-high, gradually add 1/3 cup sugar and continue whipping about 3–4 minutes until stiff, glossy peaks form. You should see firm peaks that hold shape without collapsing. Whip egg yolks: Combine the remaining 1/3 cup sugar with 1 1/2 tablespoons warm water until sugar is moistened. Add 4 egg yolks and 2 teaspoons vanilla, then beat on medium-high for about 4 minutes until the mixture lightens and ribbons fall from the whisk. Lower speed and stream in 2 tablespoons vegetable oil while mixing to emulsify. Fold batter gently: Fold half the whipped whites into the yolk mix to lighten it, then sift in the dry ingredients and gently fold until just combined. Add remaining whites and fold carefully to keep as much air as possible—stop when streaks disappear but some small air pockets remain. Bake & cool: Divide batter evenly between pans, tap lightly to release large bubbles, and run a knife to pop the biggest pockets. Bake about 20 minutes; the top should spring back slowly when pressed and a toothpick comes out clean. Immediately invert pans and tap from about 4 inches high, leaving them upside down in the pans on a wire rack to cool for about an hour—this helps prevent collapse. Apply syrup & whip cream: Mix 1/4 cup sugar with 1/4 cup boiling water until dissolved. Brush sponge tops and sides generously with the syrup. Whip 2 cups cold heavy cream with 3 tablespoons powdered sugar, 3 tablespoons cocoa, and 1/2 teaspoon vanilla to stiff peaks—do not overwhip or it will grain. Assemble: Place one sponge right-side-up, spread a thin layer of raspberry jam, arrange halved strawberries as desired, then spread a generous layer of chocolate whipped cream. Top with second sponge, cover with remaining cream, and decorate with strawberries. Chill briefly to set before slicing.

Storage Tips

Store the assembled cake refrigerated in a cake carrier or covered loosely with plastic wrap for up to 2 days — whipped cream will soften over time. If storing just layers, wrap each cooled layer tightly in plastic and then foil; refrigerate up to 2 days or freeze up to 3 months. To thaw frozen layers, transfer to the refrigerator overnight, then warm to room temperature slightly and brush with syrup before assembling. When reheating a slice, bring to room temperature for 30 minutes rather than microwaving to preserve the airy texture.

Ingredient Substitutions

If you don’t have cornstarch, substitute with an equal amount of cake flour (light protein) but reduce the all-purpose flour by 1 tablespoon. For dairy-free variation, replace heavy cream with a stabilized coconut cream whipped with 1 tablespoon powdered sugar and 1 teaspoon vanilla — texture will be slightly denser. You can swap raspberry jam for apricot or strawberry preserves; for more chocolate intensity, use a dark chocolate ganache layer or dulce de leche for a richer profile. Avoid using melted butter in place of oil — butter will create heavier, less airy layers.

Serving Suggestions

Serve this cake slightly chilled with a cup of tea or a light dessert wine. For celebrations, stack tiny piped rosettes of whipped cream around the edge and scatter fresh berries in the center. A dusting of sifted cocoa or a few curls of dark chocolate on top elevates presentation. This cake works well as a centerpiece for afternoon tea, bridal showers, or elegant brunches — its light texture makes it ideal when you want dessert that isn’t overwhelming after a multi-course meal.

Cultural Background

This style of airy layer has roots in the Victorian sponge and classic European genoise techniques where whipped eggs create lift instead of chemical leaveners or butter creaming. The chocolate sponge is an evolution that adds cocoa and a bit of coffee to heighten chocolate flavor. Across Europe this approach is prized for celebratory cakes because it allows for bright fillings and light creams rather than dense frostings, and the technique has been adapted by home bakers worldwide for its elegant mouthfeel.

Seasonal Adaptations

In spring and summer, swap the raspberry jam for a fresh strawberry compote and add thinly sliced stone fruits between layers. For autumn, use spiced pear preserves and top with toasted hazelnuts. During winter holidays, infuse the simple syrup with a cinnamon stick and a strip of orange zest for warm aromatics. These swaps allow the same light structure to carry seasonal flavors beautifully.

Meal Prep Tips

For make-ahead convenience, bake layers up to 3 days ahead and keep well wrapped. Prepare jam and chill. Whip the chocolate cream on the day you assemble for the fluffiest texture, or stabilize the cream with 1 teaspoon gelatin dissolved in 1 tablespoon warm water for longer-lasting structure if needed for events. Transport assembled cake in a fitted carrier and chill upon arrival to keep the whipped cream firm.

There’s a special satisfaction in slicing through a perfectly even, feather-light sponge and watching the jam and cream peek out. Treat this recipe as a template — once you understand the technique, you’ll find countless ways to make it your own. Enjoy sharing it with friends and family.