Today I’m going to show you how to make the most adorable buttercream Watermelon Cake and Cupcakes! These fun summertime designs are so CUTE, and you’ll love how simple they are to create!

It’s time for some summer fun! We’re actually a couple of days shy of the official first day of summer but the kids are out of school, the pool is open, & it’s HOT– so in my book, summer is well underway ;0)

When I think of summertime cake ideas, watermelon is one of the first themes that pops into my head…and somehow I’ve never made a watermelon cake tutorial before.  Today is the day!  We’re going to show you how to transform a simple sheet cake into an adorable slice of watermelon– and we’re throwing in couple of matching cupcake designs too.

First, I started with a 9×13″ sheet cake.  (Mine is one layer but of course this design works just fine with a double layer!)

I trimmed away the two bottom corners with a slight curve, as you can see below.  I also scooped away a “bite” on top of the watermelon.

*When possible (and especially if working with a soft cake), I like to do my cake carving when the cake is at least partially frozen.  If your cake is dense, room temperature cake is fine for carving.

Next, I frosted my cake with our Classic Vanilla Buttercream Frosting tinted with Americolor Deep Pink. (I carried the pink frosting across the top side of the cake also.)

Smooth the frosting however you’d like.  I used the “Hot knife” method of smoothing, so I dipped my spatula in very hot water before gliding it across my pink frosting.

Then, I frosted around the bottom edge/side of the cake with buttercream tinted Americolor Electric Green.

I swooped in with my trusty spatula at an angle and lifted away the excess icing.  I wanted a nice smooth/flat surface for the ruffles I’m about to add.

Practice makes perfect!  Especially when you’re having trouble envisioning what a ruffled rind will look like ;0) —

My ruffled rind is piped with a large Wilton 125 petal tip (green frosting), and a smaller Wilton 104 tip (white frosting).

Here we go!  You can see that I allow just a very slight overhang with my ruffles.

If you’ve never made ruffles before, just remember that the small end of the teardrop shaped piping tip is going to be facing out…and the opening is parallel to the surface of the cake as you move the bag slightly up and down to create the ruffles.  This description will make much more sense as you are doing it.

Now, our rind is complete!  Two rows of green, piped with a Wilton 125…and one row of white, piped with a 104 tip.  My seeds are oversized chocolate chips, but fondant would have worked nicely too!

Since I used a crusting buttercream, I was able to impress “teeth marks” into the bite out of the watermelon.  I did this using the fat handle of a “cake paintbrush” of mine, but you can improvise with whatever you can find around the kitchen.

Next, I made some cute little cupcakes!  The pink is piped with a Wilton 12 tip, spotted with mini chips, and then ruffled with a small petal tip.

Another simple watermelon design is create ruffles in alternating shades of green.  Again, I used a small petal tip for these green shades!

Here’s our cake and cupcakes!! As a final detail, I piped small pink dots on top of my pink frosting with a Wilton 3 tip but this is completely optional.  This was such a fun cake to make, I hope that you try it out this summer!!

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Happy Baking!