Treat yourself with this super moist Japanese sponge cake with a hint of sweetness from honey! Made with only 4 ingredients, Japanese Castella Cake is a very popular confectionery in Japan. Try this delicious cake for your weekend baking project. It makes the perfect holiday or hostess gift too.
Japanese Castella Cake, or Kasutera (カステラ) in Japanese, is a popular Japanese honey sponge cake which was originally introduced by the Portuguese merchants to Nagasaki area in the 16th century. The name is derived from Portuguese Pão de Castela, meaning “bread from Castile”. Castella is made of just 4 basic ingredients: bread flour, eggs, sugar, and honey.
A dark brown top and bottom crusts with a creamy yellow center give a beautiful contrast to the sponge cake. This delicate cake is very moist, smooth, bouncy, and has just enough sweetness with a fragrance of honey.
Watch How to Make Castella (Kasutera)
The difference between Japanese honey sponge cake and the regular western sponge cake is Japanese Castella is more delicate and bouncy in texture. It is raised solely by egg foam. There is no butter, oil or any leavening agent like salt or baking powder. It also uses bread flour (higher gluten content) instead of regular flour to achieve the result. The flavor is very light with mild sweetness. Therefore the cake is delightful to enjoy green tea or iced coffee during summertime.
You can tell by its popularity as Castella is being sold everywhere in Japan, from departmental stores, specialty sweet stores to convenience stores. They often come in a slim rectangle box in simple plastic packaging for an everyday snack or fanciful packaging for gifting.
Traditionally, Japanese Castella cake is baked slowly in a wooden frame to create a soft smooth texture for the sponge because a metal baking pan would transfer the heat too fast and it would become too dry. I assume most of you would not have a wooden frame readily available, so my Castella recipe uses a standard 1-lb loaf pan.
I searched for Castella recipes in Japanese and found hundreds of recipes available online. The majority of them use just the same 4 ingredients with slightly different measurements for each recipe. I started to experiment with measurement for each ingredient for my 1-lb loaf pan. Then I increased to two pans as my family really loves this light and moist Japanese Castella Cake for oyatsu (snack).
Before I move on to the recipe, I want to mention that it took me a very long time to finalize this recipe. Since then I have been using this exact recipe many times and it worked each time. However, please understand that everyone’s oven works differently and you may need to adjust the recipe according to your oven.
Japanese Castella Cake Baking Notes:
The key to a successful Castella is in the beating of the eggs and baking time. Even after trying many times, I still wish to improve the slight wrinkled top (Any tips, anyone?). Otherwise, the texture and flavor is just perfect!
Before I realized that I needed to create my own recipe that works for my oven, I had tried many other Castella recipes I found online. However, I failed miserably despite the beautiful pictures shared on those recipes. Here are some of the tips I learned from my experience in achieving the perfect texture:
Failure 1: A hard and dense layer formed at the bottom of the cake although the top layer turned out beautifully.
- There needs to be enough air beaten into the batter for the cake to rise. Make sure to beat the eggs based on the time specified. The texture will be thick and the color will be pale yellow. When you stop the mixer and lift the whisk attachment, the mixture should fall in ribbons.
- Sift the flour two times to loosen.
Failure 2: The cake sank in the middle during the baking, or after I pulled out from the oven.
- Bake it longer until the cake is firm and fully cooked inside.
- Do not over mix the batter when you add the flour mixture.
- Must use bread flour.
A lot of recipes suggested to bake at a higher temperature and cover the cake with the aluminum foil to prevent the cake from browning further and finish baking. However, this made the cake start to sink immediately and it didn’t work for me… Therefore, I couldn’t bake at a higher temperature than 320 ºF (160 ºC).
Some recipes suggest baking it at a higher temperature to brown the top first, then change to lower temperature to continue baking. But being unable to cover the top with aluminum foil, my only option was to bake at 320 ºF (160 ºC) and slowly brown the top without overcooking inside of the cake.
You may need to tweak my recipe in order to get the perfect result. I have also seen some recipes that require extra steps and ingredients, but I made this recipe as simple as possible without losing authentic flavor. I hope my recipe works for you and you will get to enjoy Castella with your family and friends.
I’ve also included a 3-minute Japanese Castella Cake recipe video above, so I hope you will check it out.
- 6 large eggs (at room temperature - very important!)
- 200 g sugar (1 cup)
- 200 g bread flour (1 ½ cup + 2 Tbsp) (See Notes)
- 80 ml honey (⅓ cup)
- 2½ Tbsp water (warm)
- 1 Tbsp honey
- ½ Tbsp water (warm)
Gather all the ingredients.
- Cut parchment paper to fit the baking pans (See the video for this process).
- Preheat oven to 320F (160C).
- Sift the bread flour with the sifter or a fine-meshed strainer twice. Holding the handle with one hand and tapping the strainer gently with the other, the flour will gradually sift through the strainer.
- Add 2½ Tbsp warm water to honey and whisk well.
- Fit the mixer with the whisk attachment. Crack eggs into the bowl and vigorously whisk until combined.
- Add the sugar.
- Beat the eggs and sugar on high speed (Speed 10) for 5 minutes (See Notes). The volume of the beaten eggs will increase about 4 times. The texture will be thick and the color will be pale yellow. When you stop the mixer and lift the whisk attachment, the mixture should fall in ribbons.
- Add the honey mixture into the egg mixture and whisk on low speed (Speed 2) until combined, about 30 seconds.
- Add the bread flour at three separate times: add 1/3 of the bread flour and whisk on low speed (Speed 2) for 15 seconds, then add more flour and whisk for 15 seconds. Add the last remaining portion and whisk until just combined for about 1 minute. Do not overmix.
- Spray the loaf pans with oil and spread out evenly with pastry brush.
- Put the parchment paper in the pans and make sure the paper sticks to the pans. If not, add oil and spread out evenly with a brush.
- Pour the batter into the pans (about 80% full).
- Using a skewer, draw a zigzag line to remove the air bubbles in the batter.
- Level batter in each pan by holding pan 2-inches above counter dropping it flat onto counter. Do this several times to release air bubbles.
- Bake at 320F (160C) on middle rack of oven for 35 to 40 minutes, or until golden brown and a skewer inserted in the center comes out clean (See Notes). I bake for 35 minutes and keep my oven door ajar for a few minutes then I take out the cake. When done, cake sides will pull away from pan slightly; top will be flat and feel spongy when pressed with finger.
- Mix 1 Tbsp honey and ½ Tbsp warm water in a bowl and apply the honey mixture on top of the cake with a pastry brush.
- Place a sheet of plastic wrap on the counter top. Take out the cake from the pan to the plastic wrap, top facing down. Gently peel off parchment paper.
- Immediately wrap the cake with plastic wrap to keep the moisture and while it's hot store in the refrigerator overnight (at least 12 hours), keeping the top side facing down. This will help the cake have more fine and moist texture.
To serve, slice off the sides of the cake with a sharp bread knife and cut into 3/4 to 1 inch thick slices (you get 7-8 slices total). It's better if you bring the cake to room temperature before serving. To save for later, wrap individual pieces with plastic wrap. You can store at room temperature for up to 3-4 days, 5-7 days in refrigerator, and 1 month in freezer.
Bread Flour: Castella has a little elastic bouncy texture from bread flour and all-purpose flour cannot achieve this texture.
Beating Eggs: If you beat the eggs with a handheld mixer, it will take more than 5 minutes. Also, if you have a stand mixer Water Jacket (hot water bath), use it for 1 minute while you whisk eggs and sugar. It helps with making a smooth texture for sponge cake. If you use handheld mixer, put the mixing bowl over hot water and whisk for 1 minute.
Baking Time: For our oven, the cake comes out perfectly after 35 minutes. However, each oven works differently and you will need to experiment with your own oven and adjust accordingly. It took me a few attempts to learn the right baking time and temperature.
Equipment you will need:
- 2 1-lb loaf pans (8.50 x 4.50 x 2.75 inch / 22 x 11 x 7 cm) - If you use a plan smaller than a 1 lb loaf pan, pour the excess batter into cupcake/muffin pan and bake for shorter time.
Recipe by Namiko Chen of Just One Cookbook. All images and content on this site are copyright protected. Please do not use my images without my permission. If you’d like to share this recipe on your site, please re-write the recipe in your own words and link to this post as the original source. Thank you.