Cloudburst Frosting

1/4 cup all-purpose flour

1 cup WHOLE (it has to be whole) milk

1 cup softened butter

1 teaspoon vanilla extract

2 cups sifted confectioner's sugar

In a small pan, gradually add the milk to the flour, whisking them together into a totally smooth mixture — you don't want any lumps here. 

Simmer, barely, over low/medium heat, until thick, whisking constantly so you don't get any lumps. (Do not walk away from the stove for even a minute! But, if you do get lumps, just push it all through a sieve.)  You want it to be the consistency of pudding. 

Remove from heat and let it cool for a few minutes, and then push a piece of plastic wrap down on the surface of the mixture (so a skin doesn't form).  Let it cool completely but NOT in the refrigerator (if you put it in the fridge, it won't work); this may take an hour or two or three.  

Cream together the butter and vanilla.  Add the confectioner's sugar and beat on high for several minutes until it is very fluffy.  Add the milk/flour mixture and beat until it is super fluffy.  The frosting will sometimes appear to separate when you add the milk/flour mixture, but just keep beating it on high until it whips up into smooth, fluffy clouds.

Just enough for a two-layer 8-inch cake.

From Alicia Paulson's blog, Posie Gets Cozy