Your Go-to Guide For Bento Cake: Recipe, Tools, Size & Weight

Bento cake: a perfect and one-in-all solution for no-personality, and no-Insta-ready cakes while being heavy on the wallet. You must have seen Gen Z talking about this cake a lot as it has gone viral on Instagram because of its personalized & creative decorations and small size (which kinda makes it even more cute). Typically, a bento cake is a mini cake with 4 to 8 inches, also called a lunchbox cake. Ideally, 1 person can have it, but that doesn’t stop you from sharing with someone else 😉.

When you’re getting a 4-inch cake, you’ll find it in an eco-friendly and small container, which is clean and easy to gift. And if you’re getting it for yourself, you’ll start drooling over this cake right away coz they always look so yummy and delish.

If a little teaser about this cute little cake has intrigued you, this blog will match your interest because we’re gonna talk all about bento cake: size, recipe, ingredients, and where it came from.

What is Bento Cake?

Basically, bento boxes which were used as a traditional Japanese single-portion meal for rice, fish, chicken, eggs, pickles and vegetables in a neat manner with proper presentation while encouraging healthy nutrition control. This tradition was picked up by South Korea but with a slight twist: they applied it for small-sized cakes with beautiful decorations and aesthetics, which resulted in “bento cakes aka Korean lunchbox cakes”.

It’s called Korean lunchbox cakes because it was first introduced in South Korea, and then it got popular in other countries. Where the word aesthetic comes in, Gen Z becomes incredibly interesting which is one of the biggest reasons why it is getting so much attention and spike on social media platforms. They’re highly photogenic, customizable, and come across as really cute little cakes.

When it comes to bento cake designs, you can either explore different bakery businesses on Instagram and see what kind of designs they offer. If you want a specific design, you will have to ask them if they offer made-to-order Korean lunchbox cakes.

You may also check other lunchbox ideas like “Boston Roll Sushi” which is most famous recipe among Gen Z.

All About Bento Cake Size and Weight

When it comes to bento size and weight, the standard bento cake size is 4 inches (10 cm), while the weight is somewhere between 250-400 grams (8-14 oz). It can vary depending on the ingredients, frosting, and fillings used for the cake. We have compiled a comparison table covering bento cake size in inches/cm and weight.

These are estimated values based on the standard ingredients, which are mostly used in making lunchbox cakes. So, it can slightly change if you add additional or different ingredients, but that’s a standard estimate for bento cake size in inches/cm, and bento cake calories.

All The Equipment You Need To Make Mini Lunchbox Cake

You’ve been seeing different reels of these mini cutie cakes, and now you’re hyped up to try it yourself at home, or you are thinking of starting an Insta-cakes business. No worries, you got it! All the basic equipment you need to crank out a perfectly baked and beautifully decorated lunchbox cake is mentioned below:

Baking Tools

1. 4-inch cake pans (round or square, silicone or metal)

2. Mixing bowls (at least 2–3 sizes)

3. Measuring cups and spoons

4. Digital kitchen scale

5. Whisk & spatula

6. Hand mixer or stand mixer

7. Sifter (for flour, cocoa, powdered sugar)

8. Cooling rack

Cake Preparation Tools

9. Parchment paper (to line pans)

10. Offset spatula (for frosting and smoothing layers)

11. Cake turnable

12. Bread knife or cake leveler

Decoration Tools

13. Piping bags & piping tips (round tips for writing, star tips for borders & rosettes)

14. Palette knife

15. Food coloring

16. Edible pens or stencils

17. Sprinkles, toppers, or edible glitter

Serving & Packaging Tools

18. Lunchbox-style cake boxes

19. Doilies or cake liners

20. Mini cake boards (especially if you’re gifting to someone)

Pro Tip: A 4-inch bento cake mold size is considered ideal, especially if you want sharp edges on your cake. And if you’re a complete beginner, silicone molds are the go-to option for you.

Must-Have Bento Cake Ingredients

We’re listing down every ingredient you need to follow this lunchbox cake recipe.

Now, you can 2x, 3x, 4x the quantity of ingredients based on how many 4-inch cakes you’re gonna bake. So, here we go:

Basic Sponge (4-inch)

All-purpose flour — 70 g (½ cup): When you mix it with liquid, gluten is developed as a reaction, which helps in holding the air in the mixture so that the cake rises perfectly well.

Sugar — 70 g (⅓ cup): Not only acts like a sweetener, but it also keeps the cake moist and helps in getting a golden crust while baking.

Egg — 1 large: It works as a binder for all the ingredients while adding richness and structure to the cake.

Butter or oil — 40 g (3 tbsp): You can use either of the options for best results. Butters bring a rich taste while oil gives a lighter texture.

Milk — 60 ml (¼ cup): It keeps the batter hydrated and helps in getting a smooth, creamy consistency & texture.

Baking powder — ½ tsp: The secret agent that raises the cake and helps it stay soft by releasing carbon dioxide when heated and creating tiny air bubbles.

Salt — a pinch: This is where it sums up successfully. It enhances all the flavors and balances the sweetness.

Vanilla extract — ½ tsp: It’s a secret ingredient, don’t tell anyone 🤫. After you’ve mixed all the ingredients, this adds aroma, which becomes heavy on the smell of egg.

Frosting Options

Whipped cream — 100 ml (½ cup): Best for Korean-inspired bento cake designs.

Buttercream — 100 g (½ cup butter + 1 cup powdered sugar): If you wanna go with detailed decorations and piping, this is the way to go.

Cream cheese frosting — 100 g cream cheese + 50 g butter + ½ cup powdered sugar: It balances the sweetness of the soft sponge with a slightly tangy, creamy flavor.

Allergy-Friendly Swaps

Eggless option: ¼ cup yogurt or 3 tbsp applesauce instead of 1 egg.

Vegan option: Plant-based milk + vegan butter + coconut cream frosting.

Gluten-free option: 1:1 gluten-free flour blend instead of all-purpose flour

Easy Bento Cake Recipe [Step-by-Step]

Baking the sponge of this snack-sized cake is unimaginably easy. Here’s how to do it:

Step 1: Bake The Cake Base

You have to mix all the sponge ingredients listed above and prepare a smooth batter. Once you’re done, use parchment paper in a 4-inch bento cake mold and grease it with the oil or butter. Then, shift the batter in the mold and bake it in the oven. And what if you don’t have one? Uh-oh! Don’t worry, we have got you covered.

That brings us to the 4-inch bento cake recipe without oven in which you’ll be using your stove. You have to preheat a heavy-bottomed pan or large pot with a lid, place a stand inside and cook the cake pan on low heat (like a mini oven).

Step 2: Slice and Layer with Frosting/Filling

Once the cake is cooled down enough, slice it into thin layers. Then, you can add any frosting or filling you have prepared i.e. whipped cream, buttercream, jam, or ganache between layers.

Step 3: Crumb Coat and Frost

At this point, you have to apply a very thin layer, which is the “crumb coat”, of the frosting to seal crumbs. Let it chill for about 10 minutes and then frost smoothly all over the cake.

Step 4: Decorate

Now, this is where your lunchbox cake art is going to shine. You can decorate it however you want with pastel piping, sprinkles, write personalized messages, mini figurines, fruit or floral touches. Literally, however you want. Then, pack it in a takeout-style box to give it the classic lunchbox style. Voila! An aesthetic and Insta-ready lunchbox cutie cake is there 🎂.

The Bottom Line

These mini cakes are all about cuteness, creativity and portability, in a nutshell. So far, you know how the concept of this cake got introduced in South Korea and made its debut in other countries as well. You have the bento cake recipe guidelines and ingredient lists, just try it out. Or you can first order it from an Instagram shop or a convenience store nearby. And you’ll be surprised to see that it’s just not the presentation, but the taste that makes it so lovable and you wanna have it again and again.

There’s nothing sweeter than this tiny treasure cake for someone if their birthday is here and the family is out of town. You can make it special for them with just ONE lunchbox cake. How cool is that? These are the small moments we’re living. Don’t let `em slide, make them special!

FAQ—Frequently Asked Questions