Avoid Pinterest Fails: How to Frost the Perfect Cookie Monster Cupcake

— -- Did you ever see a beautiful treat on Pinterest, tried to make it and failed spectacularly?

Melissa Rycroft did just that this morning on “Good Morning America,” revealing the results of her Rainbow Cake in a Jar and Cookie Monster cupcake experiments.

Sonja Foust told “GMA”’s special correspondent just where she went wrong with the Rainbow Cake.

People typically put too much batter in the jar, Foust said, adding that jars should only be filled to the halfway point. Jars filled to more than two-thirds will overflow, she said.

Another mistake people make is using store-bought batter, she said. Because that batter is typically thinner, the colors tend to bleed together. She recommended that people make their own cake batter.

She also said people should make sure their jars are placed in pans filled with water during baking, saying that this helped keep the colors bright.

"GMA" chef and food stylist Karen Pickus gave her tips for how you can frost the perfect Cookie Monster cupcake. Click here to get her recipe!

Frosting Tips for Cookie Monster Cupcake

1. Your cupcakes must be completely cooled before you try to frost them.
2. Use an ice cream scoop to mold frosting into a dome shape. Place the frosting dome on top of the cupcake. This serves as the base for the blue Cookie Monster hair and face and makes it much easier to create the face.
3. For the blue hair, use decorator’s frosting. It has the correct stiffness to allow each strand of hair to stand up. Regular frosting is a bit too creamy to hold up.
4. Use the correct frosting tips. This is really important. In order to get the perfect cookie monster hair, you need a tip with tiny holes in it. You can get these at specialty baking stores.
5. If you don’t have the correct frosting tip, many recipes recommend taking a zip-lock bag and poking six holes in one corner using bamboo skewers and using this to make the hair. We think this is too hard!
6. Refrigerate immediately after piping the frosting out.