Step by Step Guide to a Perfect Fluffy Castella Cake
This cake may look delicate, but it’s very doable with a little care. Follow these steps exactly and you’ll get a perfectly risen, smooth topped sponge with no cracks or collapse.
Ingredients
6 egg whites
6 egg yolks
85 g sugar (superfine or caster is ideal)
80 ml vegetable oil
90 g cake flour or sponge flour
70 ml milk
¼ tsp salt
Instructions
1: Whip the Meringue
In a clean, dry bowl, beat the egg whites until they become foamy.
Gradually add sugar and continue whipping until stiff peaks form the meringue should be glossy and stable.
2: Prepare the Batter Base
Heat the oil for 90 seconds in the microwave or gently on the stove. It should be warm but not boiling.
Add sifted flour and salt into the warm oil and mix until smooth.
Stir in the egg yolks and milk, mixing until you have a silky, lump free batter.
3: Fold in the Meringue
Take one third of the meringue and gently mix it into the batter to loosen it.
Then, fold in the remaining meringue in two more additions, using a spatula and gentle motions to keep the batter airy.
4: Pour and Tap
Pour the batter into a parchment lined square or loaf tin (avoid greasing the sides).
Tap the tin on the counter several times to remove air bubbles that might cause holes during baking.
5: Water Bath Baking
Place the cake tin inside a larger baking dish and fill the outer dish with hot water halfway up the sides.
Bake in a preheated oven at 150°C (300°F) for about 60 minutes, or until the center springs back and a toothpick comes out clean.
6: Cool and Slice
When done, gently bang the tin on the counter a few times to release steam and prevent shrinking.
Let the cake cool completely in the tin, then transfer to a cutting board and slice with a serrated knife.
This light and airy Castella sponge cake is baked to golden perfection with a delicate crumb
Pro Tips for Castella Success
Techniques That Make a Difference
This isn’t your average sponge cake the method is part of what gives Castella its signature bounce and cotton soft bite. Here are tips I follow every time:
Use room temperature eggs: They whip better and give more volume.
Don’t overheat the oil: Just warm enough to blend the flour, but not hot enough to scramble the yolks.
Always sift your flour: Even a few lumps can weigh the cake down or cause streaks.
Fold, don’t stir: Keep your motions slow and careful to avoid deflating the airy meringue.
Bake low and slow: High heat causes cracking 150°C and steam creates that smooth, glossy top.
Need more steam based bakes? Check out our delicate milk custard rice cake or the beautifully jiggly Japanese cheesecake that uses a similar water bath method for texture that wows.
Creative Castella Cake Twists
This cake is stunning in its simplicity, but here’s how I love to experiment with flavors without compromising texture:
Matcha Castella: Add 1 teaspoon of sifted matcha powder with the flour for a subtle earthy twist.
Honey infused: Swap out 1 tablespoon of sugar for honey for a deeper golden crust and natural sweetness.
Lemon version: Add 1 teaspoon of lemon zest and a tiny splash of lemon juice for a bright finish.
Layered with jam: Slice the cake horizontally and add a thin spread of fruit jam or citrus marmalade between layers.
Mini Castella bites: Bake the batter in cupcake molds using the same water bath method for adorable, single serve treats.
Want more cake creativity? Our 3 ingredient sponge cake is perfect for fast flavor experimentation, and the Greek yogurt cake offers a rich but tangy spin on light cake recipes.
