As a 29-year-old, I know that I should have outgrown the cartoons I grew up watching…but I simply can’t help it.

I loved SpongeBob then, and I love him now. I may love him forever. There’s something about his ever-optimistic personality and his appreciation for the little things in life that still resonates with me.

I’ll admit, I still watch SpongeBob on Saturday mornings. In fact, I get up early (before my husband, who is not as big of a fan!) to watch it while I bake.

I’ve even seen SpongeBob on Broadway!! Which is a fantastic show, I highly recommend seeing it.

Clearly, it was high time I made a SpongeBob cake. Like so many other fun ideas, a SpongeBob cake had been on my cake to-do list for years.

There was a big special on Nickelodeon for SpongeBob’s birthday this July (I’m embarrassed that I know that), and it was gave me the push I needed to finally make this cake.

I was determined to do him justice, to make him proud. I also wanted to make him primarily out of buttercream, with as little fondant as possible.

There’s nothing wrong with fondant, I just love working with and eating buttercream more 🙂

I implemented some interesting techniques to make it work, but I’m happy with how he turned out!

Who Lives in A Pineapple Under the Sea?

I had to incorporate pineapple into this cake, since SpongeBob lives in one! To do this, I added some pineapple juice into my layer cake recipe.

I also made a pineapple simple syrup, to make sure the flavor was prominent in each bite.

I knew I’d have to do a lot of work with the buttercream to get the decoration of this cake right, so I chose not to add pineapple into the frosting.

If you wanted to go all out with the pineapple theme, you could add crushed, freeze-dried pineapple into your frosting.

Another option would be to add pineapple slices between the cake layers, sealed in with a frosting dam.

However, this can cause the layers to slice when they’re being frosted! That’s the main reason I chose not to use fresh fruit.

I knew this would end up being a tall, thin cake, which can already be difficult to assemble and frost.

Who’s Porous As He?

As I frosted SpongeBob, I was trying to figure out the best way to give him holes.

I really wanted them to be three dimensional as opposed to just adding spots onto the cake, or little fondant circles.

While saying it here sounds strange, SpongeBob’s circles are actually a unique shade of green on TV.

Originally, I thought I would use a small circle cutter to cut out circles of buttercream. I planned to use some olive-green buttercream to fill inside the circles.

I waited to make his holes until the rest of the cake was decorated.

When the time came, using green frosting just felt wrong. In the end, I used a completely different technique.

I heated up a small baby spoon with some hot water (and dried it), and used that to carve out holes in the cake.

The cake had been chilled overnight and the buttercream had crusted, so the warm spoon worked like a charm!

It also gave me the 3D look I was going for, without having to incorporate any green frosting.

Giving SpongeBob a Backbone

In true invertebrate form, SpongeBob needed a little help sitting up. Since he’s built with 6 rectangular cake layers, he isn’t the most stable cake shape.

I used two bubble tea straws to ensure he stayed upright while I decorated him. You also could use a wooden dowel.

I prefer bubble tea straws because they’re so much easier to cut.

I highly recommend adding some sort of central support into this cake, to keep the layers in place.

This cake had to be chilled several times throughout its decoration. Knowing that it was stable gave me piece of mind as I took it in and out of the fridge.

SpongeBob’s Squeaky Shoes

The other piece of this cake that I struggled with was SpongeBob’s shoes. They needed to be 3D as well, but are such a unique shape.

The last thing I wanted to do was plop two giant pieces of fondant onto the cake board. I worked so hard to create him with buttercream, and I wasn’t ready to quit that just yet.

Whenever I need to make an interesting shape to add to a cake, I used cake scraps mixed with frosting.

This allows me to essentially make a cake pop in whatever shape I need!

I saved the cake scraps from leveling my sheet cakes, and mixed them with a combination of chocolate buttercream, and black gel food coloring.

Once the mixture was fully combined and evenly colored, I shaped his shoes onto cut bits of bubble tea straws.

The straws help them stay upright once they’re placed on the cake board.

Then I popped his little shoes in the freezer!! Freezing them makes them easier to handle and add to the cake. It also helps them set and keep their shape.

Let Me Know What You Think!

If you (or your child) loves SpongeBob as much as I do, please let me know what you think of this cake.

Or better yet, try the recipe and let me know how yours turns out!!

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