I used white cake mix and made it according to the box. I love to add an extra egg and pudding mix. Then I was trying to go for a sea-green which didn't turn out quite the color I was going for but to do that you need blue and yellow food coloring.
I poured the batter into greased pans (like I said I used 1 bundt pan and 1 8 inch cake pan but 2 cake pans would be fine). I wanted it to be taller/ look like cascading effect so I thought the bundt pan would be helpful. Then let cool and flip out of the pans. ⭐ TIP: If you need to trim any cake to help them lay flat, just use a serrated knife. For the frosting I just used cans of white frosting (always grab extra to make sure you have enough). I like to add a little cream cheese for some homemade taste. Then a few drops of blue food coloring to get the ocean color you like.
If you are using two cake pans, just cut a little circle in the middle of each (reserve the cake you removed). The bundt pan obviously already is good. Place one cake on a plate or platter. Frost the top and then add the other half of the cake. Slowly and carefully add the mermaid into both holes.Crumble the reserved cake into the hole and around the barbie to help hold her in place.
Next frost the cake on the sides and on the top. And up the mermaid body just a bit.
I crushed graham crackers in my food processor to make "sand". Add some graham crackers around the mermaid to make it look like she is sitting on the sand. Then I added it around the base of the cake, too.
For the mermaid tail, I picked out the color M&.M's I wanted to use and alternated them with them slightly sticking up to look like scales. Continue down, get a little slimmer, then go back out to make the fin.
Then a I added a few embellishments with edible starfish, seashells, etc. I also use mermaid colored sprinkles.