Cute Lunch box Cakes with Whipped Cream Frosting (Bento Cakes)

Lunch box cakes, also known as Korean bento cakes, are mini versions of full sized cakes.  Perfect for a beginner baker, they’re simple in design and easy to decorate.  My step by step instructions will create the most incredibly delicious and fluffy cake!  Frosted with fresh whipped cream, this lunch box cake is super light and fit for up to two people (or…maybe just yourself)!

What are Lunch box Cakes?

Originating from South Korea, lunch box cakes are just smaller versions of regular sized cakes.  They are usually between 3 – 4 inches (I prefer 3.5 inches) and 2 – 3 tiers.  The key characteristic is that a lunch box cake fits into a clamshell container similar to a burger takeout box.  This makes them really easy to transport as gifts.  

They typically boast minimalistic designs and give out a cute homemade charm.  Frost these mini cakes with whipped cream or buttercream and decorate with sprinkles, rosettes and/or candies – whatever you like!  Add a sweet message and put a smile on someone’s face!

Why make a Lunch box Cake?

I first discovered lunch box cakes when I was looking for ideas for my daughter’s birthday.  With the pandemic, a lunch box cake was perfect to share amongst just our family.  It was also a nice treat to give out to family and friends who couldn’t celebrate with us in person. Since then, I’ve found so many other uses for lunch box cakes!   But really, do we need to have any reason/excuse to eat cake? 

Practice for new bakers 

If you’re new to cake making and decorating, a lunch box cake is an economical and less wasteful way to practice!  These cakes are smaller and easier to handle so you can improve those layering and decorating chops.  It avoids the disaster of piping a rosette for the first time on your daughter’s actual birthday cake – the night before…(thank goodness pics can be taken to show only one side of a cake)

Small gatherings

Sometimes you don’t need a 6 inch cake.  A 4 inch cake is the perfect size (for those post covid pounds).  They are also great to be served alongside a dessert table for variety! (Side note: I personally embrace cake leftovers)

Gifting (especially during Covid)

With the transportability of a clamshell takeout box, these lunch box cakes are prime for giving away.  Not to mention, way more economical than splurging on cake boxes.  Brighten up someone’s day by dropping one of these off 🙂

Party favours

Cupcakes are all the rage for party favours, but why not give a mini lunch box cake instead?  You can turn up the fanciness and uniqueness all at once.  Plus, no one can resist a cute take home cake especially from a baby shower 🙂 

Cake smash

If the idea of splurging on a custom ten person cake (only to get your 1 yr old bust their fist into it) makes your wallet cry, a lunch box cake might be the answer.  You can also customize it just the way you like it and have a few as backups for your photoshoot.

Kids activity

Crafting and decorating anything is always met with squealy excitement in our house.  Why not let your kids layer, pipe and decorate a mini cake fully loaded with their heart’s desire?  Let them spark their creativity and develop those fine motor skills!

How to Make Lunch box Cakes

You can pretty much follow any regular cake recipe.  Just make sure you use a 13”x 9” pan for lunch box cakes.  I followed the RecipeTin Eats Vanilla Cake recipe because of the beautiful plush and almost cottony texture similar to Japanese sponge.  It’s also super easy to make and stays moist for days. Aside from a good tasting cake, it helps if you’re planning on baking and decorating on separate days.

As an alternative, my banana cake recipe, also produces a super fluffy, moist and soft crumb!

Cake Baking Tips

I followed the instructions pretty closely along with some of my tips listed below:

• Grease and line your 9”x13” baking pan and then cover with parchment paper at the bottom and all 4 sides.  I crisscrossed two large parchment paper pieces to do this.
• A standing mixer makes things easier than a hand mixer for aerating the eggs.  You will also have both hands free to combine your dry ingredients into your wet mixture.
• Use glass measuring pitchers for the flour mixture and the hot butter milk to make for easy pouring.
• Watch your cake after the 25 minute mark and start checking for doneness and to avoid overbaking.
• Read all the instructions before starting. 
• Preheat your oven before you start, since this cake comes together fast!

Whipped Cream Frosting Instructions

Step 1:  Place a stainless steel bowl and whisk/beaters in the fridge for at least 15-20 minutes (a cold bowl ensures success).  Alternatively, set your bowl on top of a bigger bowl with some ice.

Step 2:  Pour the whipped cream into the bowl and whisk on high for about 1 minute.

Step 3: Add the powdered sugar, vanilla extract and salt and continue whisking.

Step 4: When soft peaks start to form, add the whipped cream stabilizer (if using)

Step 5: Continue whisking on high until you start to see stiff peaks.  Change to low speed and continue whisking.  Watch carefully, as the whipped cream will come together fast.  Overmixing will create butter.

Step 7:  Once the whipped cream is formed, scrape down the sides of the bowl with a spatula and mix thoroughly

How to Assemble Lunch box Cakes

Step 1: Cut out 3 pieces of 5 inch x 5 inch parchment paper.  These will serve as your base for decorating.

Step 2: Once the cake is cooled completely, use a 3.5 inch cookie cutter and cut out 6 rounds.  

Step 3: Carefully remove the cut out cakes and choose 2 pieces for each cake.  I usually play around with the 6 cut outs, stacking them in pairs to make sure I get 3 level cakes.  If they are slightly slanted, you can level it out with frosting.

Step 4: On a piece of parchment paper, place a dab of whipped cream and place your cut out.  

Step 5: Brush on some soaking syrup (if using) and spread some frosting on top.

Step 6: Place a second cut out on top and check to make sure it’s level.

Step 7:  Go frost happily!  Frost the top and sides and smooth it out with a spatula or a bench scraper.  Since the cake is so small, I just rotated the cake using the piece of parchment paper to get a smooth look.

Step 8:  You can leave it clean or add sprinkles, candy or pipe a design!

Decorating Tips for Success

• Use cookie cutters to cut out the shapes.  You will have leftover cake pieces (which I shamelessly ate for snack after) or can use to make cake pops
• Use a soaking syrup to ensure a moist sponge – especially if you’re making these ahead of time.
• Anchor your first tier and keep it from moving by putting some whipped cream or buttercream on the parchment paper under your cake tier.
• If your frosting gets runny, pop your cake and frosting in the fridge for about an hour to solidify again. Rewhip your frosting for a few minutes to get the consistency and resume decorating.
• Add a crumb coat (thin coat of frosting) if you want to make sure no crumbs end up on your frosted design. I found this specific cake recipe didn’t create too many large crumbs while frosting and I didn’t need it.
• If you want to make piping designs, like rosettes, I’d recommend buttercream since it crusts a bit after to reduce smearing.
• When decorating lunch box cakes, keep in mind the takeout container it goes in.  Add fruit slices or “flat” designs on top of the cake and not ones that stick up too much.  I wouldn’t add a design higher than ½ above the top of the cake.  
• I would recommend using buttercream or whipped cream frosting for this cake.  The small size of these cakes can’t hold up to fondant. 
• Clean up any frosting smears on the parchment paper by wiping it with a damp paper towel.  The bottom edge doesn’t have to look perfect since they will be “hidden” in the lunch box container.

Decorating Ideas for Lunch box Cakes

Let your creative juices flow! If you need some inspiration, here are some ideas:

• Smooth frosting with a piped message.
• Covered entirely with sprinkles of your choice.
• Covered entirely with piped mini rosettes.
• Smooth frosting with a piped border on top of the cake. Use your favorite piping tip (star, round etc) and put evenly sized dollops all around the border. Add a message too!
• Frost entire cake as smoothly as possible and using a fork, drag it gently straight across making pin stripes. Wipe and repeat. Don’t drag the fork too deep into the cake!
• Use different colored frostings and create painted marble effects.
• Smooth frosting with slices of fruit on top.
• Smooth frosting on the sides with scalloped frosting on top.
• Smooth frosting on the sides with hatched design frosting on top.

If the end look doesn’t look great, you can easily smooth out the frosting and try again!

Packaging Tips

• Always cut out a piece of parchment paper 1 inch larger than your takeout box and decorate your cake on that. The paper is also crucial for transferring your cake into the takeout box.
• The bottom part of the cake doesn’t need to look perfect because the cake box hides any imperfections.
• Test out your design in your takeout box and make sure it doesn’t get squished when you close the lid.
• Add a ribbon and a cute message on the takeout box if it’s a gift!

Storing Tips

• Once frosted and finished, place your finished cakes in their lunch boxes and store it in the fridge.  I would recommend storing it this way for up to 24 hrs. 
• If you’re storing them longer – up to 48 hours, I would recommend putting them in an airtight container instead of the takeout box. Transfer to a takeout box right before.

Freezing Instructions

• Freeze cake layers just like regular cakes. Airtight in plastic wrap into a ziploc bag. Store flat.
• Buttercream can be frozen in an airtight freezer bag.
• Whipped cream shouldn’t be frozen and made the day of frosting.
• Thaw cake layers and butter cream overnight in the fridge and put at room temperature 1 hour before decorating.

Frequently Asked Questions