Castella (Kasutera) is a classic Japanese sponge cake with Portuguese roots, known for its fine, tight crumb and gentle honey sweetness. This recipe uses the traditional hot milk and honey method to create a moist, tender cake that doesn’t dry out quickly. It’s simpler than it looks—with just a few staple ingredients and careful folding, you’ll get a professional-quality cake at home.
Ingredients
- 6 large eggs (about 300 g / 10.5 oz), room temperature
- 1 cup (200 g) granulated sugar
- 1 cup (120 g) bread flour (or all-purpose, but bread flour gives a chewier texture)
- 2 tbsp (40 g) honey
- 2 tbsp (30 ml) whole milk
- 1/2 tsp vanilla extract (optional)
- 2 tbsp (30 g) unsalted butter, melted (for greasing)
- Parchment paper for lining
Instructions
- Preheat your oven to 320°F (160°C). Line a 9×5-inch (23×13 cm) loaf pan with parchment paper, leaving some overhang on the long sides for easy removal. Grease the pan lightly with butter or oil.
- Separate the eggs: place the whites in a large, clean mixing bowl and the yolks in a separate small bowl. Let both come to room temperature if not already.
- In a small saucepan, warm the milk and honey over low heat until the honey dissolves and the mixture is warm to the touch (about 100°F / 38°C). Do not boil. Remove from heat and set aside.
- In the large bowl, beat the egg whites with an electric mixer on medium speed until foamy. Gradually add the sugar, 1 tablespoon at a time, while continuing to beat. Increase speed to high and beat until stiff, glossy peaks form (the meringue should hold a peak that bends slightly at the tip, not dry). This takes about 5–7 minutes.
- Add the egg yolks one at a time to the meringue, beating on low speed just until combined after each addition. Scrape down the sides and bottom of the bowl.
- Sift the flour over the egg mixture in three additions, folding gently with a spatula after each addition until no streaks of flour remain. Be careful not to deflate the batter.
- Pour the warm milk-honey mixture along the side of the bowl and fold it in gently, just until incorporated. The batter will become slightly runny but should still be airy.
- Pour the batter into the prepared pan. Tap the pan on the counter a few times to release large air bubbles. Use a skewer to swirl the batter gently to break up any remaining large bubbles.
- Bake for 45–55 minutes, or until the top is deep golden brown and a skewer inserted into the center comes out clean. The internal temperature should read 200°F (93°C) if you use an instant-read thermometer (this is a sugar-rich cake, so it’s done when the center reaches this temp).
- Remove from the oven and immediately cover the pan with plastic wrap (this helps keep the cake moist and prevents the top from cracking). Let it cool in the pan for 10 minutes.
- Lift the cake out using the parchment overhang, then wrap it tightly in plastic wrap while still warm. Let it cool completely at room temperature, then refrigerate for at least 2 hours (or overnight) before slicing. This step is crucial for a clean cut and proper texture.
Tips
- Use bread flour: Bread flour has more protein, which gives castella its characteristic dense, chewy crumb. All-purpose works, but the texture will be softer and more cake-like.
- Don’t overfold: When adding flour and milk, fold until just combined. Overmixing deflates the batter, resulting in a heavy, dense cake.
- Chill before slicing: Refrigerating the cake overnight makes it much easier to slice thin, even pieces. Use a serrated knife and wipe it clean between cuts.
- Substitute honey: If you don’t have honey, use golden syrup or maple syrup. The flavor will change slightly, but the cake will still be moist.
Serving Suggestions
Serve castella at room temperature or slightly chilled. It’s delicious on its own with a cup of green tea or coffee. For a dessert, top with fresh whipped cream and berries, or toast lightly and spread with butter. In Japan, it’s often enjoyed as a snack with milk.
Variations
- Matcha Castella: Replace 1 tablespoon of flour with 1 tablespoon of matcha powder, sifting it together with the flour.
- Chocolate Castella: Replace 2 tablespoons of flour with 2 tablespoons of cocoa powder.
- Brown Sugar Castella: Substitute the granulated sugar with light brown sugar for a deeper, molasses-like flavor.
- Add-ins: Fold in 1/2 cup of chocolate chips, dried fruit, or chopped nuts at the end of mixing.
Storage and Reheating
Store castella in an airtight container at room temperature for up to 3 days, or in the refrigerator for up to a week. For longer storage, wrap tightly in plastic wrap and freeze for up to 1 month. To serve, thaw in the refrigerator overnight or at room temperature for a few hours. Reheat slices in a toaster oven at 300°F (150°C) for 3–5 minutes, or microwave for 15 seconds, to refresh the texture.
Frequently Asked Questions
Why did my castella sink in the middle? This usually happens if the batter was overmixed, deflating the air, or if the oven temperature was too low. Make sure your oven is properly preheated and use an oven thermometer. Also, avoid opening the oven door during baking.
Can I use cake flour instead of bread flour? Yes, but the texture will be more delicate and less chewy. If using cake flour, reduce the amount to 3/4 cup (90 g) and sift it well.
My cake is too dense and heavy. What went wrong? The most common cause is not beating the egg whites enough. They need to reach stiff peaks. Also, make sure you fold gently and don’t overmix.
Can I make this without an electric mixer? Yes, but it will be a workout. Whisk the egg whites by hand until stiff, which can take 10–15 minutes. Make sure the bowl and whisk are completely clean and free of grease.
Why does my castella have a crust that’s too thick? A thick crust usually means the oven temperature is too high. Try lowering it to 300°F (150°C) and baking a little longer. Also, covering with plastic wrap while cooling helps soften the crust.
Can I double the recipe? Yes, you can double all ingredients and bake in two loaf pans or one 9×13-inch (23×33 cm) pan. Adjust baking time: start checking at 40 minutes for the larger pan.
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- Simmering in Cultural Traditions: A Hearty Stew
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Safety notes: safe minimum internal temperatures from USDA FSIS; raw and undercooked fish guidance from the U.S. FDA. Food safety notes
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