Fluffy Castella Sponge Cake – Light, Airy & Perfectly Sweet

Make this recipe your own with these fun twists:
Matcha Castella : Add 1–2 tbsp matcha powder to the flour mix.
Chocolate Castella : Substitute 2–3 tbsp flour with cocoa powder.
Citrus Zest : Add lemon or orange zest to the batter for a bright twist.
Honey Glaze : Brush warm cake with a light honey glaze for extra sweetness.
Layered Version : Cut horizontally and fill with whipped cream or jam.