My son loves sharks, so it was no surprise when he asked for a shark birthday party.
Of course he wanted a shark cake and fun shark party games to celebrate.
I searched everywhere to find just the right cake, but they all included miniature toys sharks or were just round cakes with a toothy shark grin. He wanted one that was 3-dimensional.
It took a bit of tinkering, but eventually I figured out how to make a shark cake. 
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This fun cake is perfect for a shark party or to do as a shark week activity.
DIY Shark Cake
Materials Needed:
- 2 Boxed Cake Mixes
- 3 – 16 oz. Cans of White Frosting
- 16 inch round cake pan
- Serrated Knife
- Marshmallows
- Black Decorator Icing
- Large Tray (to display cake)
When making a shaped cake like this, a pound cake mix works best because it doesn’t crumble as easily when you cut it. However, you can choose another flavor (we did chocolate).
Follow the directions on your cake mix, then pour both cake batters into your 16 inch round cake pan.
Since most box mixes don’t have directions for how long to cook the cake, you will need to check it often after it’s been in the oven for 25 minutes.
Once your cake is cooked, let it cool completely. This is very important, as a warm cake will fall apart when you cut it.
How to Make a Shark Cake
Once the cake is completely cooled, it is time to start assembling your homemade shark cake.
If you baked a cake that is something other than a pound cake, such as the chocolate cake we made, you will want to pop it into the freezer for 15 minutes or so. This will help you cut the cake with less crumbling.
Use a serrated knife to cut the circular cake down the middle with an “S” shape. It should look like a yin-yang shape (or 2 paisleys side by side).
Half of the cake will become the base of the shark.
Use your serrated knife to cut the circular portion off the second paisley shape. This will form the top of the shark’s head.
Use frosting to secure the circle onto the circular portion of the shark’s base.
Then cut the pointy part off the other half of cake. Use your serrated knife to carefully cut this pointed piece in half horizontally to create 2 side fins for your shark. Use frosting to attach them to the cake. (See photo below.)
Finally, cut a triangular piece from what was left to make the shark’s tail and another to be its dorsal fin. (Tip: Use a serrated knife to tapper the sides of your triangles so they are thinner on top. This will help them stand up better.)
Use icing to stick the dorsal fin and tail onto the shark’s base. (You may want to wait to do this until it is close to party time, as they are fragile pieces. I actually used a few carefully hidden toothpicks to hold up the tail.)
We used blue food coloring to color the remaing white frosting. You could also make it grey or leave it white.
Carefully cover the cake with your frosting. For a more finished look, use fondant icing. (We have food allergies here, so we stuck with basic frosting.)
To make eyes, cut thin slices from marshmallows and stick them in place. Use black decorator icing to make the pupil.
Then cut a few more marshmallows into triangles to form teeth.
Finish the mouth by outlining it with black decorating icing.
This shark shaped cake was a huge hit at my son’s birthday party.
He had fun comparing it to the creatures in his favorite shark books for kids.
I’m sure your own shark fan will love it, too.
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