Smooth Cake Frosting

Usually when I throw a birthday party, I end up posting some sort of cake tutorial. I thought I'd post how to get smooth frosting, especially on a tall layer cake like the rainbow cake I made for Amelia's birthday.

The first trick is to crumb-coat your cake. You do this by spreading a very thin layer of frosting (use your normal buttercream recipe, but add a little more liquid than normal to make it just a tad thinner) over the whole cake (make sure your cake is COMPLETELY cool first!). Don't worry if you get a bunch of crumbs in the frosting - that's the point of the crumb coat.

Let the crumb coat dry - I baked, assembled, and crumb-coated Amelia's cake the night before and then stuck it in the fridge until the next morning. Even better than the fridge is a cool, dry spot in the house.

Then, once it has dried, pipe (I used a zip-lock bag with a corner cut out) thicker frosting over the entire cake like this

You can see the crumb coat underneath on the left.

This will help you make sure the frosting is distributed evenly, and is the easiest way I've found to get frosting to look good on the sides of a tall cake. Then use a large flat knife or metal cake-decorating spatula to smooth it out. The trick here is to put it into warm water between strokes. This keeps the frosting from sticking to the metal and also the warmth helps spread the frosting smoothly.

And there you go! :)