Our Korean lunchbox cake recipe is a mini-size sponge cake decorated with a cute minimalistic aesthetic.
A lunchbox cake is happiness in a box. While finding joy in the little things is the goal for most of us, dessert lovers can indeed find it in this adorable Korean dessert. Often decorated with dreamy embellishments, this eye-catching confection has been flooding Pinterest and Instagram feeds lately. Be it for a casual picnic or a little celebration, it will surely sweeten up your day.
For our bento cake recipe, we'll show you how to make a chocolate sponge cake with buttercream frosting. We'll also share some of our favourite decoration tips so you can replicate the similar aesthetics and cute appeal at home.
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What size is a lunchbox cake?
Living up to its name, it is bento-sized. The most common Korean lunchbox cake size is 4 inches, weighing 350 grams. However, they are also available in bigger sizes, such as 6 inches and 8 inches. For our recipe, we'll make a 6-inch diameter lunchbox cake with two layers.
The Korean lunch box cake box and container add a charm to the appeal. Whether your dessert is circular or heart-shaped, it will be in a clamshell takeout container. Despite the fancy decorations on the treat, the simple container gives a more minimalistic vibe.
Bento cake frosting
When it comes to frosting for your bento cake, you can choose to make either whipped cream or buttercream. These two options are the most popular ones out there.
However, buttercream is preferred as it does not require refrigeration like whipped cream. Buttercream also has a smooth and creamy texture, whereas whipped cream is delicate and airy.
Our Korean bento cake recipe uses a regular buttercream made with unsalted butter and icing sugar.
Lunchbox Cake Recipe | Korean Bento Cake
Ingredients
For the chocolate sponge cake base
- 3 eggs
- 150 g sugar
- 150 g unsalted butter
- ½ teaspoon vanilla essence
- 150 g self-raising flour
- 2 tablespoon cocoa powder
- ¾ teaspoon baking powder
- 2 tablespoon milk
- pinch salt optional
For vanilla buttercream frosting
- 150 g unsalted butter
- 150 g powdered sugar
- ½ teaspoon vanilla extract
- 2 tablespoon hot water
- food colouring optional
- decorative icing optional
Equipment
Cooking Instructions
- Preheat the oven to 190°C/170°C fan. Spread a little bit of butter on the base and sides of a 6-inch cake tine and line them with baking parchment paper.
- Sift caster sugar, self-raising flour and cocoa powder into a mixing bowl. Then, add softened unsalted butter, eggs, baking powder, vanilla extract, milk and salt. Whisk all the ingredients together until well combined and smooth.
- Pour the cake batter into the cake tin and bake it in the oven for 30 mins or until the centre is completely cooked. To test if it's cooked, poke in a toothpick or skewer through the centre of the cake. If it comes out clean, then the cake is cooked.
- While the cake is baking, let's make the buttercream. Sift icing sugar into a mixing bowl and add softened butter. Beat the mixture using a spatula or hand whisk until it becomes smooth. This process takes about 5 minutes to complete by hand, so be patient. Once the buttercream is smooth, you can add vanilla extract, any food colouring, and hot water. We add the hot water to loosen the buttercream slightly to make it easily spreadable later. Mix until well combined and smooth. Place the buttercream in the fridge while we prepare the cake.
- Remove the cake from the oven, and allow it to cool for at least 20 minutes. Then, cut off the top crust and slice it it horizontally to make it it into two even layers.
- Assemble the lunchbox cake. Spread buttercream on each layer and apply the first coat of frosting. After 15 minutes, add the final frosting, decorate and serve.
Recipe Notes
- Baking time may differ depending on your oven. If the cake is not cooked after 30 minutes, return it to bake for another 5-10 minutes.
- If you want to save time, we recommend using a hand mixer when beating/mixing the buttercream. However, while it takes some elbow grease to mix the buttercream, you have better control of getting a smooth and creamy texture if you do it by hand.
- Our recipe is for a basic lunchbox cake, but feel free to be creative in presenting your frosting. You can also add chocolate, strawberry, matcha, or other types of flavourings.
Nutrition
Calories have been calculated using an online calculator. Nutritional information offered on Honest Food Talks is for general information purposes and is only a rough estimate.
Bento Cake Cooking Tips
The baking time of a lunchbox cake will depend on the baking dish used. To prevent overbaking, be sure to check your dessert once it's been in the oven for 25 minutes.
We like to poke it using a toothpick to check if the cake is thoroughly cooked. If the toothpick comes out relatively clean, then it's ready. However, if the toothpick comes out wet, you may need to leave it in the oven for another 5 - 10 minutes.
If you are short of time, you can prepare the buttercream frosting up to a week in advance and store it in a refrigerator in an airtight container. Once you're ready to use it, bring it to room temperature and re-whip it beforehand.
You can use gel food colouring to create bright-coloured frostings. We used a combination of blue pea butterfly powder and blue gel food colouring to make the one in the photos.
Korean Lunchbox Cake Decoration Tips
The key to decorating a Korean lunchbox cake is that less is more. Unlike decorated cakes we typically see in bakeries, the Korean style is usually plainer, and any design is smaller. Here are some of the common points when you decorate your lunchbox cake:
- Use only 1 - 2 colours for decorating or a max of 3 colours.
- Try and pick a light pastel base colour.
- Pick a cute icon or symbol that you can use to make small, repetitive designs across the cake.
- Place it in a clamshell takeout box or on top of some parchment paper to add to the aesthetic.
Following these principles, we decorated our cake using blue vanilla buttercream to make a light blue sky and piped on small clouds using white frosting.
Common Flavours
Korean sweet snacks are often vanilla or chocolate-flavoured. These are the go-to flavours as they often complement the taste of the frosting. However, they can also come in other flavours, including more extravagant ones such as lemon, Biscoff, and matcha. Since they are customisable, you can come up with any flavour for this confection.
Calories
A small serving of this adorable treat contains about 500 calories. So, despite being small like other Asian snacks, such as Chinese mooncakes, don't be fooled—it packs a punch!
How did your frosty and sweet dessert turn out? Share with your lovely home masterpieces by posting a photo and tagging us on Instagram at @honestfoodtalks.
Have you heard of Honey Toast? They are the next dessert craze from Japan and Korea that has captivated home bakers across the globe. Check out our recipe on how to make them at home.
Quinton
Mine came out absolutely adorable. Love the tips here!
Yunes
I love the recipe, thank you so much! just I don't understand what is ovalette? I never hear about that in my country.
Greetings from Mexico!
Laura
Ovalette is a stabilizer used in baking sponge cakes. It helps the eggs to rise rapidly and stiffly. As it is acidic it also helps the beaten eggs to remain stable and not lose the airy and voluminous texture. It makes sponge cake softer and smoother. Ovalette can be purchased at Malaysian markets, or on Amazon.
Ephue
Cake turned out so cute! Hard to pipe but little flowers but I am happy