Fluffy Castella Sponge Cake
Introduction
Castella sponge cake is a classic, elegant cake known for its smooth surface, fine crumb, and delicate sweetness. Originating from traditional sponge techniques, it has a more compact and velvety texture than Western sponge cakes, yet remains lighter than pound or butter cakes. This balance makes Castella uniquely soft, moist, and refined.
Description
This Castella sponge cake is tall, fluffy, and evenly textured with a tender, cloud-like bite. It has a mild sweetness, subtle richness from egg yolks and oil, and a beautifully smooth crumb that slices cleanly. Perfect on its own or paired with tea, coffee, or fruit.
Ingredients
6 egg whites
6 egg yolks
85 g (⅓ cup + 1 tbsp) granulated sugar
80 ml (⅓ cup) vegetable oil
90 g (¾ cup) cake flour / sponge flour
70 ml (¼ cup + 2 tbsp) milk
¼ tsp salt
Instructions
- Prepare the pan and oven
Preheat oven to 150°C / 300°F.
Line the bottom and sides of a 20 cm (8-inch) square or round pan with parchment paper.
If possible, prepare a water bath (recommended for even baking). - Mix the yolk batter
In a bowl, whisk egg yolks and half of the sugar until pale.
Add vegetable oil and milk, whisking until smooth.
Sift in cake flour and salt.
Mix gently until lump-free and silky. - Whip the egg whites
Beat egg whites until foamy.
Gradually add the remaining sugar.
Beat until soft to medium peaks form (glossy and slightly curved tips). - Combine
Gently fold one-third of the egg whites into the yolk batter to loosen it.
Carefully fold in the remaining egg whites in two additions.
Use slow, gentle motions to preserve air. - Bake
Pour batter into prepared pan and tap lightly to release large air bubbles.
Place pan in a water bath.
Bake for 60–70 minutes until the top is golden and springs back gently when touched. - Cool
Remove cake from oven and water bath.
Let cool slightly, then lift out using parchment.
Peel paper carefully and allow to cool completely before slicing.
Tips for Success
Use room-temperature eggs
Do not over-whip egg whites
Fold gently to maintain structure
Low, slow baking prevents cracking
Water bath ensures even moisture
Optional Additions
½ tsp vanilla extract
Honey (replace 15 g of sugar)
Lemon zest for a fresh note
Light dusting of powdered sugar after cooling
Nutritional Information (Approx. per slice)
Calories: 170
Protein: 5 g
Fat: 9 g
Carbohydrates: 17 g
Light, low-butter cake
Conclusion
Castella sponge cake is a beautiful example of simplicity done right. With just eggs, sugar, flour, and oil, it delivers a refined texture that feels both light and satisfying. Its balanced structure makes it a timeless favorite across generations.