Japanese Sponge Cake Recipe

Quick Summary: Japanese sponge cake is a light, fluffy foam cake made from just 5 ingredients (eggs, sugar, cake flour, milk, and butter) with no leavening agents, relying entirely on whipped whole eggs for its airy rise. It takes about 20 minutes of hands-on time and bakes into a tender, melt-in-your-mouth layer perfect for strawberry shortcake, birthday cakes, and other Japanese-style desserts.

If you have already mastered Italian Pan di Spagna, Genoise cake, and chocolate sponge cake, it is time to take you on an adventure with Japanese sponge cake.

Japanese cake: sponge cake vs. cotton sponge cake

Both Japanese sponge cakes are egg-rich and low in flour, but they differ in preparation and texture.

Japanese sponge cake gets its rise from whipped whole eggs and sugar, creating a lighter, slightly drier crumb. Japanese cotton sponge cake uses a meringue made from whipped egg whites and is baked in a water bath, resulting in a softer, moister texture.

Both are classic Japanese cakes loved for their delicate texture and flavor.

Why you'll love this recipe

• Just 5 simple ingredients. Eggs, sugar, cake flour, milk, and butter are all you need for a bakery-quality sponge.
• Light and fluffy texture. The whipped-egg method gives you a soft, airy, melt-in-your-mouth crumb every time.
• Quick hands-on time. It takes about 20 minutes of active work before the oven takes over.
• Endlessly versatile: The perfect base for strawberry shortcake, birthday cakes, layer cakes, and other Japanese-style desserts.

Ingredients

For ingredients and detailed instructions, refer to the recipe card below.

• Eggs: Use whole eggs at room temperature for the best results. Bring eggs to the counter an hour before making the cake. Using a digital scale when weighing the eggs is essential to ensure accurate measurements.

• Sugar: The recipe calls for caster or baker's sugar. Authentically, Japanese sponge cake is made with fine-grained granulated sugar. You can make it yourself: process regular granulated sugar in a food processor a few times.

• Flour: Use cake flour, which has a lighter protein content than all-purpose flour. In Japan, soft, very fine flour with a low protein content (6.5±0.5%) is used to make sponge cakes. It also has a low ash content (0.35%) and enhances the flavor of eggs and dairy products.

• Butter brings flavor, taste, and moisture to the sponge cake. Opt for high-quality unsalted butter with 82% fat content.

• Milk is another ingredient that provides moisture to the cake.

Recipe variations

• Add 0.35 oz. (10 g) of trehalose to make the sponge cake finer-textured and moister. Trehalose is a natural sugar made from yeast and is about 45% as sweet as regular sugar.
• Add 0.35 oz. (10 g) of dried strawberry powder to create a strawberry sponge cake.
• Replace 2 tablespoons (31 g) of butter with 1 oz. (28 g) of Taihaku sesame oil, maximizing the cake's flavor and delivering a delicate, melt-in-the-mouth texture.

How to make Japanese sponge cake

Step 1: Preheat the oven to 390°F (200°C). Sift flour through a flour sifter into a clean mixing bowl and set aside.

Step 2: Place butter and milk in a small bowl over a container of hot water and warm them to 122°F (50°C).

Step 3: Grease a 6-inch (15 cm) springform pan with softened butter, dust with flour, and remove excess. Or line the bottom of the pan with a parchment paper circle and the sides with parchment strips.

Step 4: Place whole eggs and granulated sugar in a heat-resistant bowl or the bowl of a stand mixer. Whisk a few times using a hand whisk (photo 1).

Step 5: Bring the bowl over a bain-marie or water bath, and beat with a handheld mixer at medium speed until the temperature reaches 97°F to 100°F (36°C to 38°C), 104°F (40°C) at maximum.

Pro tip: For the best results, keep 97°F (36°C) in summer and 100°F (38°C) in wintertime.

Step 6: Remove the bowl from the hot water bath, and beat with an electric or stand mixer at high speed for 8 minutes (photo 2).

Step 7: Lower the speed to medium and beat for 1 minute. Then switch to low speed and beat for the remaining 2 minutes. The egg mixture must triple in volume and reach a ribbon stage (photo 3).

Pro tip: If using a hand mixer, turn the bowl counterclockwise with an undominant hand to adjust the texture of the dough. Coarse air bubbles will crush, and the finished cake will get the perfect texture.

Step 8: Stop the mixer and stick a toothpick into the beaten eggs. If it holds upright, you are done with whipping (photo 4).

Step 9: Add the sifted cake flour, sifting it again over the bowl, and gently mix it with a rubber spatula. Turn the bowl counterclockwise and scoop the batter from the bottom of the bowl until the flour disappears.

Pro tip: Regarding spatula movements, it has to draw the letter "J," passing the bottom of the bowl from 2 to 8 o'clock, lifting the batter, and returning it.

Step 10: Add a scoop of the batter to a bowl with milk and butter preheated to 122°F (50°C), then mix with a spatula.

Pro tip: For the best results, the milk and butter mixture must be at 122°F (50°C); if lower, it will sink and won't mix well.

Step 11: Pour the cake batter back into the main bowl, and scoop the batter from the bottom of the bowl with a rubber spatula. Turn the bowl counterclockwise at the same time.

Step 12: Pour the batter into the prepared mold, then tap the bottom of the mold lightly on the table to remove air bubbles (photo 5).

Pro tip: Coarse air bubbles are easy to crush, and the finished product will be poor, so prepare the texture well.

Step 13: Lower the oven temperature to 340°F (170°C) and bake for 27-30 minutes.

Pro tip: Check the oven temperature with an oven thermometer for accurate baking results.

Step 14: Remove the baking pan from the oven and tap the mold from about 4 inches (10 cm) against the table to prevent it from shrinking. Let the cake cool in the pan for 5-10 minutes (photo 6).

Step 15: Turn the mold upside down on a wire rack and let it cool for 5 minutes. Then turn it over so the grilled side faces up, and let it cool with the paper still on until it is completely cooled.

Expert Tips

1. Use a kitchen scale that provides the most accurate measurements and baking results.
2. To make an 8-inch (20 cm) cake, multiply the recipe ingredients by 1.78 or use this simple cake pan converter. You may need to adjust the baking time.
3. Follow the recommended temperature carefully to bake the perfect sponge cake.
4. Gently incorporate the flour into the batter to retain its lightness and prevent deflation.
5. Bake the batter without delay to ensure optimal results.
6. Don't open the oven door during baking.
7. To ensure evenly smooth layers, allow the cake to cool before slicing. For easier slicing, wait until the day after baking.
8. To slice a cake, use a cake knife, a long serrated knife, or a cake leveler for perfectly even slices.
9. Soak the cake layers when assembling: this type of sponge has a drier texture than a moist vanilla sponge cake.

What to serve with Japanese sponge cake

Japanese sponge cake pairs beautifully with light, fresh flavors. Layer it with lightly sweetened whipped cream and fresh strawberries to make a classic Japanese strawberry shortcake, or serve simple slices alongside seasonal fruit such as peaches, mango, or berries.

It is also lovely with a dusting of powdered sugar next to a cup of matcha, hojicha, or coffee, and can be brushed with a simple syrup and filled with pastry cream for a more elegant dessert.

Why is my Japanese sponge cake dense?

A dense or deflated sponge usually comes down to how the eggs are whipped and folded. Since this cake rises in the air alone, a few simple habits keep it tall and fluffy like a light Genoise cake.

• Whip the eggs fully. Beat the eggs and sugar until pale, thick, and tripled in volume, since this trapped air is what makes the cake rise.
• Fold gently. Add the flour in batches and fold with a light hand so you do not knock out the air you just whipped in.
• Bake right away. Get the batter into a preheated oven quickly, as a batter that sits too long loses volume and bakes up flat.
• Do not open the oven early. A sudden temperature drop can make the delicate structure sink, just as you would with a Swiss roll sponge.

Storing & freezing

Store Japanese sponge cake, well wrapped in plastic wrap, in the refrigerator for 2-3 days. You can freeze it, covered with plastic wrap and aluminum foil, for 3 months.

Recipe FAQ

What is Japanese sponge cake made of?
Japanese sponge cake is made with just 5 ingredients: eggs, sugar, cake flour, whole milk, and butter. It closely resembles the famous Genoise sponge cake.

How do you make Japanese sponge cake fluffy?
The key is whipping whole eggs and sugar over a warm water bath until the mixture triples in volume and reaches the ribbon stage. Fold in the flour gently, and add the warm milk-and-butter mixture last so the batter keeps its airy structure.

What is the difference between Japanese sponge cake and cotton sponge cake?
Japanese sponge cake is a drier cake that rises from whipping whole eggs with sugar, while Japanese cotton sponge cake uses a stiff meringue of separated egg whites and yolks and is baked in a water bath for a moister, cottony texture.

Can I use all-purpose flour instead of cake flour?
Cake flour is best because its low protein content keeps the crumb light and tender. If you only have all-purpose flour, replace 2 tablespoons per cup with cornstarch to mimic cake flour, though the texture will be slightly less delicate.

Why are Japanese cakes so good?
Japanese cakes are known for their velvety texture and delicate sweetness. The secret lies in a lengthy egg-whisking process that yields a soft, fluffy texture that practically melts in your mouth.

Why are Japanese cakes different?
Japanese cakes are lighter and less sweet than Western-style cakes. They boast a delicate, airy texture and are made with fresh whipped cream rather than heavy buttercream.

Why did my sponge cake shrink or deflate?
Shrinking usually means the egg foam has lost air. Whip the eggs to a stable ribbon stage, gently fold in the flour, and put the batter in the oven right away. As soon as it comes out, tap the pan firmly against the counter to set the structure and prevent it from collapsing as it cools.

Why is my sponge cake cracked or wrinkled on top?
Cracks and wrinkles come from an oven that is too hot or from over-mixing that traps large air bubbles. Lower the temperature as directed, use an oven thermometer for accuracy, and tap the filled pan on the counter before baking to release coarse bubbles for a smoother top.

Love sponge cake recipes? Try these next!

If you enjoy this Japanese soft cake, you will also love the other plain sponge cakes on the website.

• Italian sponge cake
• Genoise Sponge Cake
• Korean Sponge Cake

Want more delicious and beautiful recipes? Subscribe to my newsletter and follow me on Facebook, Pinterest, and Instagram for my latest updates. If you make this recipe, please leave a star rating on the recipe card and comment below!

Print

Recipe card

The nutritional information has been calculated using an online recipe nutrition calculator such as Verywellfit.com and is intended for informational purposes only. These figures should be used as a general guideline and not be construed as a guarantee.