Learn how to make an easy flat Minion cake with this step-by-step DIY tutorial—perfect for kids’ birthdays and beginner bakers!

Easy Flat Minion Cake in 5 Simple Steps – Perfect for Kids’ Birthdays

This easy flat Minion cake comes together in just five simple steps—ideal for beginner bakers or anyone short on time. I’ve used every shortcut I know to make it a breeze, including buttercream instead of fondant to speed things up without sacrificing charm. It all began on a lazy Sunday afternoon when Frankie’s new obsession with Minions—those cheeky, banana-loving yellow characters from Despicable Me—sparked the idea. With their silly antics and gibberish language, it’s no wonder kids adore them!

 Step 1: Find the Perfect Flat Minion Cake Design

When I set out to create a Minion birthday cake for Frankie’s second birthday, the first thing I did was search for inspiration. While there were plenty of Minion cake ideas online, many looked far too complicated for what I had in mind. I wanted a simple, achievable design—an easy flat Minion cake that still had that wow factor kids adore.

Back when my own children were little, I crafted many of their birthday cakes from a well-loved copy of the Women’s Weekly Children’s Birthday Cake Book. The treasure chest, packed with lollies, was always a hit, while the swimming pool cake, with jelly water that famously melted mid-picnic, was definitely the most ambitious!

Now, I’m baking for the next generation. This sweet little DIY Minion cake is my first for delightful Frankie, who just turned two. Happy birthday, Frankie!

To keep things simple, I used a pre-ordered half slab vanilla sponge from Woolworths—only $20 and the perfect base for a flat Minion cake with buttercream. Bake it the day before decorating to make shaping and icing much easier.

Step 2: Easy Minion Birthday Cake Ingredients with Buttercream Icing

For this easy flat Minion cake, I’ve kept the ingredients list as simple as possible—perfect for busy parents or beginner bakers. Here’s what you’ll need:

  • ½ slab vanilla sponge cake (pre-ordered from Woolworths bakery)

  • 2 packets Queen Buttercream Mix

  • 1 packet Designer Icing in black

  • Queen Classic Yellow and Blue Food Colouring

  • Strip liquorice for detail

I opted for buttercream icing over fondant for this Minion birthday cake because it’s quicker to work with and much more forgiving. The vivid yellow and blue tones that bring the Minion to life are also easier to achieve when mixed into a soft buttercream base.

While you can make buttercream from scratch, I used a packet mix to save time—just add butter, and you’re ready to go. It results in a smooth, spreadable icing that’s ideal for this flat Minion cake design.

Draw a minion around the same size as the cake slab

Step 3: Sketching the Shape for Your Flat Minion Cake Design

To bring your flat Minion cake to life, you’ll need to sketch out your design first. Using a photo of a Minion birthday cake as a reference, I drew my Minion onto a sheet of baking paper, matching the size of the pre-ordered slab cake. I allowed extra space at the top and bottom to give the design a balanced look.

My Minion shape is slightly narrower than the sponge base, which works perfectly—those leftover cake offcuts didn’t go to waste. In true family tradition, they’re destined for a trifle, much to K2’s delight!

Once I had the shape drawn, I cut it out and used it as a stencil to guide the trimming. The arms, legs, and feet were cut separately from thinner portions of the cake to give the easy flat Minion cake a playful, slightly three-dimensional appearance without the complexity of layered carving.

A liquorice outline helps keep the buttercream icing in the right places.

Step 4: Outline Your Easy Flat Minion Cake with Liquorice Strips

A simple trick to make your flat Minion cake look sharp and well-defined is using liquorice strips to outline the key features—glasses, overalls, and gloves. Not only does this add great visual detail to your Minion birthday cake, but it also acts as a clever barrier to stop the buttercream icing colours from blending into each other.

To keep the lines crisp, I carefully placed the liquorice after icing each section, using tissues and a wooden skewer to tidy up any stray dabs of colour. It’s an easy but effective way to make your DIY Minion cake look professionally finished, even with minimal effort.

Carefully ice the minion cake.

Step 5: Decorate Your Flat Minion Cake with Buttercream Icing

Now it’s time to bring your easy flat Minion cake to life with buttercream icing. This step takes a little patience, but it’s surprisingly simple once you get into the rhythm. The key is to work with one colour at a time and be careful not to drip or smudge icing onto sections you’ve already finished—slow and steady wins the race!

For the finishing touches on this Minion birthday cake, I added three little liquorice hairs on top of his head and used a few slices of fresh strawberry to create a cheeky tongue. These little details really make your DIY Minion cake pop with personality.

And the best part? Seeing the pure joy on Frankie’s face when she recognised her favourite character. One delighted smile and a gleeful “Minion!” was more than enough to make every step worth it.

This minion just needs hair and a tongue.

The Joy of Making a Simple Minion Cake

Creating this easy flat Minion cake was not only fun and achievable, but also a sweet way to celebrate a little one’s big day. With a few smart shortcuts—like using buttercream icing, a pre-made sponge, and liquorice for clean lines—you can whip up a charming Minion birthday cake without the stress or fuss of fondant or complex carving.

Whether you’re a seasoned cake-maker or trying your hand at your first DIY Minion cake, this design is a guaranteed crowd-pleaser. And at the end of the day, it’s not about perfection—it’s about the smiles, the laughter, and the joy of sharing something homemade with love.

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