Korean castella cake is a pillowy-soft, honey-sweetened sponge cake with a fine, moist crumb that practically melts in your mouth. Unlike its Japanese cousin, the Korean version uses a water bath and a lower oven temperature, which yields an incredibly tender, almost custard-like texture. This recipe uses the classic method of whipped egg whites folded into a rich yolk batter, then baked low and slow for that signature tall, jiggly result.
Ingredients
- 6 large eggs, separated (cold for whites, room temperature for yolks)
- 1/2 cup (120 ml) whole milk, room temperature
- 1/4 cup (60 g) unsalted butter, melted and cooled
- 1 tbsp (15 ml) honey
- 1 tsp vanilla extract
- 3/4 cup (95 g) cake flour, sifted
- 1/2 cup (100 g) granulated sugar, divided
- 1/4 tsp salt
- 1/4 tsp cream of tartar (optional, for stability)
Instructions
- Preheat your oven to 300°F (150°C). Grease an 8-inch (20-cm) round cake pan and line the bottom with parchment paper. If using a springform pan, wrap the outside tightly with aluminum foil to prevent water from seeping in during the water bath.
- In a large bowl, whisk together the egg yolks, milk, melted butter, honey, and vanilla extract until smooth and well combined.
- Add the sifted cake flour and salt to the yolk mixture. Whisk gently until the batter is smooth and free of lumps. Set aside.
- In a separate clean, dry bowl, beat the egg whites with an electric mixer on medium speed until foamy. If using, add the cream of tartar. Gradually add the sugar, 1 tablespoon at a time, while beating on high speed. Continue until stiff, glossy peaks form—when you lift the whisk, the peaks should stand upright and not droop.
- Gently fold one-third of the beaten egg whites into the yolk batter using a rubber spatula. Once mostly incorporated, fold in the remaining whites in two additions. Be careful not to deflate the mixture; fold just until no white streaks remain.
- Pour the batter into the prepared pan. Tap the pan gently on the counter a few times to release any large air bubbles.
- Place the cake pan into a larger roasting pan. Pour hot water into the roasting pan until it reaches about halfway up the sides of the cake pan. This water bath helps the cake bake evenly and keeps it moist.
- Bake for 60–70 minutes, until the top is golden brown and a toothpick inserted into the center comes out clean. The internal temperature of the cake should read about 200°F (93°C) if measured with an instant-read thermometer—this ensures the eggs are fully set.
- Turn off the oven and leave the cake inside with the door slightly ajar for 10 minutes. This gradual cooling helps prevent the top from cracking.
- Remove the cake from the water bath and let it cool in the pan on a wire rack for 15 minutes. Then carefully remove the cake from the pan, peel off the parchment, and let it cool completely on the rack.
Tips
- Use cake flour: Cake flour has lower protein content than all-purpose, which gives the cake its tender crumb. If you substitute all-purpose, replace 2 tablespoons (about 16 g) with cornstarch to mimic cake flour.
- Room-temperature ingredients matter: Cold eggs can deflate the batter. Separate the eggs while cold, then let the yolks come to room temperature and the whites sit out for 20–30 minutes before whipping—they beat to a more stable foam.
- Don’t overmix: When folding the egg whites, use a gentle hand. Overmixing deflates the air and results in a dense, rubbery cake. Stop as soon as the batter is uniform.
- Water bath is essential: The steam from the water bath keeps the oven humid, preventing the cake from drying out and cracking. If you skip it, the cake will be drier and may sink in the middle.
Serving Suggestions
Korean castella cake is delicious on its own, but you can elevate it with a dusting of powdered sugar or a drizzle of honey. Serve it warm or at room temperature with a cup of green tea or coffee. For a dessert, pair it with fresh berries and a dollop of whipped cream. It also makes a lovely base for trifles or as a side to fruit compote.
Variations
- Matcha Castella: Replace 1 tablespoon (about 8 g) of the cake flour with matcha powder, sifting it together with the flour.
- Chocolate Castella: Substitute 2 tablespoons (about 16 g) of cake flour with unsweetened cocoa powder.
- Citrus Castella: Add 1 tablespoon of lemon or orange zest to the yolk mixture for a bright, fresh flavor.
- Honey-free version: If you prefer not to use honey, replace it with an equal amount of maple syrup or light corn syrup, though the flavor will change slightly.
Storage and Reheating
Store leftover castella cake in an airtight container at room temperature for up to 2 days, or in the refrigerator for up to 4 days. The cake will firm up when chilled, so let it sit at room temperature for 15 minutes before serving. To reheat, wrap a slice in a damp paper towel and microwave for 10–15 seconds, or warm in a 300°F (150°C) oven for 5 minutes. You can also freeze the cake for up to 2 months; wrap tightly in plastic wrap and thaw overnight in the refrigerator before serving.
Frequently Asked Questions
Why did my cake collapse in the middle? This usually happens if the egg whites were under-whipped or overmixed, causing the batter to lose air. Also, opening the oven door during baking can cause a sudden temperature drop. Make sure to whip the whites to stiff peaks and fold gently, and keep the oven closed until the cake is nearly done.
Can I use a hand mixer instead of a stand mixer? Yes, a hand mixer works perfectly. Just be sure to beat the egg whites long enough—about 5–7 minutes on high—until they form stiff peaks that hold their shape.
What if I don’t have cake flour? You can make a substitute: for every 1 cup of all-purpose flour, remove 2 tablespoons and replace with 2 tablespoons of cornstarch. Sift together three times to combine well.
How do I know when the cake is done without a thermometer? Insert a toothpick into the center; if it comes out clean or with only a few moist crumbs, it’s done. The top should be golden brown and spring back lightly when touched.
Can I make this cake without a water bath? You can, but the texture will be less moist and the top may crack. If you skip the water bath, reduce the oven temperature to 280°F (138°C) and bake for about 55–65 minutes, checking for doneness.
Why is my cake too dense? Overmixing the batter after adding the flour can develop gluten, making the cake tough. Also, if the egg whites weren’t beaten enough, they won’t provide enough lift. Ensure you fold gently and beat the whites to stiff, glossy peaks.
Related
- Pink Zebra Simmering Light: DIY Stovetop Wax Recipe
- New Year Hair Simmering Color: DIY Recipe
- New Year’s Eve Hoppin’ John: Black-Eyed Peas and Rice for Luck
More recipes to cook
Safety notes: safe minimum internal temperatures from USDA FSIS; raw and undercooked fish guidance from the U.S. FDA. Food safety notes
Spotted an error? Tell us and we will correct it (corrections policy).