This recipe delivers a cake that is both simple and refined. Castella’s texture is unlike typical sponge cakes—it’s moist, yet airy, with a fine, uniform crumb. It’s sweet but not overpowering, making it ideal for pairing with tea or coffee. The honey not only adds depth of flavor but also keeps the cake tender for days. What truly sets this cake apart is its clean finish, elegant appearance, and the fact that it tastes even better the next day. It’s a perfect dessert to prepare in advance for guests or special occasions.
Ingredients
(Tip: You’ll find the full list of ingredients and measurements in the recipe card below.)
1 tbsp coarse sugar (turbinado or similar) 100 g bread flour 20 g cake flour 3 egg whites (approx. 35 g each) 120 g white caster sugar 4 egg yolks (approx. 17 g each) 40 g honey 30 ml whole milk 30 ml neutral cooking oil (e.g., canola)
Directions
Preheat the Oven: Preheat your oven to 180°C (356°F). Line an 18 cm (7-inch) square cake pan with baking paper and sprinkle coarse sugar evenly over the bottom.
Sift the Flours: Sift the bread flour and cake flour together. Set aside.
Whip the Egg Whites: In a clean bowl, whip the egg whites on low to medium-low until foamy. Add sugar in 3–4 parts, mixing well after each addition. Increase speed and continue whipping until stiff peaks form.
Add Egg Yolks and Honey: Add the egg yolks one at a time, briefly whipping to incorporate each. Drizzle in the honey and whip for 10 more seconds.
Fold in the Flour: Sift one-third of the flour mixture into the batter. Fold gently to maintain volume. Repeat until all the flour is incorporated.
Mix Oil and Milk: In a small bowl, whisk together the milk and oil. Add 2–3 tablespoons of the batter to this mixture, whisk until combined, then fold it back into the main batter.
Prepare to Bake: Pour the batter into the prepared pan. Use a skewer to draw zigzag lines horizontally and vertically across the surface to release air bubbles. Tap the pan lightly on the counter.
Layered Baking Process: Place on the top oven shelf and bake for 1 minute. Remove, draw lines again, and return to the top shelf. Repeat this two more times. After the third time, move the cake to the middle shelf, bake for 7 minutes, then reduce the heat to 160°C (320°F) and continue baking for 30–40 minutes. Start checking doneness at 25 minutes. The cake is done when a skewer comes out clean.
Cool and Rest: Drop the pan gently on the counter once to prevent shrinking. Cool slightly, then wrap the cake (with baking paper still on) in plastic wrap while it’s still warm. Place upside down in an airtight container and rest for 12–24 hours before slicing.
Serve: Trim the edges, slice into thick pieces, and serve.
Matcha Castella: Add 1 tbsp of matcha powder to the flour mixture for a green tea flavor.
Brown Sugar Castella: Substitute part of the sugar with Japanese kurozato or dark brown sugar for deeper richness.
Yuzu Castella: Add 1 tsp of yuzu zest for a refreshing citrus twist.
Chocolate Castella: Mix in 1 tbsp of unsweetened cocoa powder to the dry ingredients for a subtle chocolate flavor.
Layered Castella: Bake in thinner layers and stack with whipped cream or bean paste between for a layered presentation.
Mini Loaves: Divide batter into smaller loaf pans for individual servings.
Almond Castella: Add a few drops of almond extract for a nutty undertone.
No Honey Version: Use maple syrup or corn syrup as a honey substitute.
Vegan Adaptation: Use aquafaba in place of egg whites and plant-based ingredients (texture will differ).
Dairy-Free Version: Swap out the milk for almond or soy milk.
Storage/Reheating
Store Castella in an airtight container at room temperature for up to 3 days. For longer storage, keep it refrigerated for up to 1 week. Let it come to room temperature before serving. Avoid reheating in the microwave, as it may dry out the cake. Instead, enjoy it as-is or warm gently in a low oven if preferred.
FAQs
What makes Castella different from other sponge cakes?
Castella uses no baking powder; its rise comes entirely from whipped egg whites. It also includes honey and both bread and cake flours, which create a unique moist-yet-structured crumb.
Why does Castella need to rest before serving?
Resting helps the cake’s texture settle, moisture redistribute evenly, and flavors—especially the honey—deepen for a richer taste.
Can I use all-purpose flour instead of bread and cake flour?
You can, but the texture may not be as light or structured. Using a mix of bread and cake flour gives the best result.
Why do I have to draw zigzag lines in the batter?
Drawing zigzag lines helps burst air bubbles and spread the batter evenly, which creates a uniform crumb and prevents holes in the finished cake.
Can I skip the coarse sugar at the bottom?
Yes, but the coarse sugar provides a signature light crunch and sparkle to each slice.
Is Castella overly sweet?
No, it’s delicately sweet with a mellow honey flavor that pairs perfectly with tea or coffee.
Can I freeze Castella?
Yes, wrap slices tightly in plastic wrap and freeze for up to 1 month. Thaw at room temperature before serving.
Can I make this cake gluten-free?
While it’s possible using gluten-free flour blends, the texture will differ. Bread flour’s structure is key to the traditional feel.
What type of honey works best?
Mild-flavored honeys like clover or acacia are ideal, as they don’t overpower the cake’s subtle profile.
Why did my Castella collapse after baking?
This could be due to overmixing, underbaking, or sudden temperature changes. Dropping the pan gently on the counter post-baking helps prevent shrinkage.
Conclusion
Japanese Castella Cake is a beautiful expression of simplicity and technique. With its moist crumb, golden top, and refined flavor, it’s a dessert that rewards patience and precision. Whether served plain, with tea, or as a thoughtful gift, this classic sponge cake offers a timeless elegance that continues to charm. Rested and sliced the next day, it becomes even more delightful—proof that some things truly get better with time.
Japanese Castella Cake (Kasutera) is a traditional sponge cake with a moist, bouncy texture and delicate honey flavor. Made without chemical leaveners, it rises entirely from whipped egg whites and careful folding techniques, resulting in a fine, uniform crumb and a shiny golden top. Best enjoyed after resting overnight.
Author:Amy
Prep Time:20 minutes
Cook Time:40 minutes
Total Time:1 hour (plus 12–24 hours resting)
Yield:16 slices
Category:Dessert / Cake
Method:Baking
Cuisine:Japanese
Diet:Vegetarian
Ingredients
1 tbsp coarse sugar (turbinado or similar)
100 g bread flour
20 g cake flour
3 egg whites (approx. 35 g each)
120 g white caster sugar
4 egg yolks (approx. 17 g each)
40 g honey
30 ml whole milk
30 ml neutral cooking oil (e.g., canola)
Instructions
Preheat oven to 180°C (356°F). Line an 18 cm square pan with baking paper and sprinkle coarse sugar over the bottom.
Sift bread flour and cake flour together. Set aside.
Whip egg whites on low to medium-low until foamy. Add caster sugar in 3–4 parts, whipping until stiff peaks form.
Add egg yolks one at a time, lightly mixing after each. Drizzle in honey and whip for 10 seconds.
Sift one-third of the flour mixture into the batter. Fold gently to maintain volume. Repeat until all flour is incorporated.
Whisk milk and oil together. Add 2–3 tablespoons of batter to this mixture, combine, then fold back into main batter.
Pour batter into pan. Use a skewer to draw zigzag lines horizontally and vertically. Tap pan lightly.
Bake: Top oven shelf 1 min, remove and redraw lines, repeat 2 more times. Move to middle shelf, bake 7 min, reduce to 160°C (320°F), continue 30–40 min. Check doneness at 25 min; skewer should come out clean.
Drop pan gently once to prevent shrinking. Cool slightly, wrap (with paper) in plastic, invert in airtight container, rest 12–24 hrs.
Trim edges, slice thickly, and serve.
Notes
Matcha Castella: Add 1 tbsp matcha powder to flour.
Brown Sugar Castella: Substitute part of sugar with dark brown sugar.
Yuzu Castella: Add 1 tsp yuzu zest.
Chocolate Castella: Add 1 tbsp cocoa powder.
Layered Castella: Bake thin layers, stack with cream or bean paste.
