What buttercream recipe would you recommend for cupcakes that isn't going to crust?

I've never used either but a non-crusting buttercream that many people on this site use are the Swiss and Italian Meringue buttercreams. They make smooth, shiny, attractive icing. The taste, I suppose, is all relative...some people like, some people don't.

I love Buttercream Dream. The recipe is under the recipe section.

Italian Merengue Buttercream for sure.
5 egg whites, 5/8 teaspoon cream of tartar, 1 1/4 cup sugar, 1/2 cup plus 2 tablespoons water 1 pound butter.
Be sure that the room isn't too too hot (you don't want to do this in the summer with no air conditioning...the butter cream could break down.

Allow the butter to come to room temperature.

Beat the eggwhites in a stand mixer withe the whisk attachment until foamy, Add the cream of tartar, beat until soft peaks form, then gradually beat in 1/4 cup of sugar until firm peaks form. Combine the sugar and water in a small pot. Heat over medium heat and stir constantly until boiling. Place a thermometer in the liquid and heat until 248 to 250 degrees farhenheit. About 1/3 of the syrup over the merengue, and beat for a few seconds. Stop the mixer and add another 1/3 of the syrup and beat for a few seconds, stop the mixer, add the rest of the syrup and beat until cool. This may take a while (as long as 15 minutes...or more, depending on the size of the mixer bowl and the temperature of the room). Switch to the paddle attachment, beat in the butter 1 tablespoon at a time. The butter cream may look curdled at some point, but by the time all the butter is added it will be a rich thick butter cream. You can flavor this with up to 8 oz of melted and cooled chocolate (bittersweet, milk or white). You can also add a little liqueur. (2-3 tablespoons)...or some fruit puree.

It will keep at room temperature up to 2 or 3 days. If you refrigerate it it will be very very hard when cold, but will re soften when it returns to room temp. REbeat the butter cream to restore the texture...but never beat it when it is cold or it will break down...only rebeat it at room temperature. This buttercream, once properly made will really hold up at room temperature for quite a long time.

try the mock buttercream recipe. it's easy enough to make for cupcakes. i even use it for cakes when am lazy and cannot be bothered to make SMBC.

I use IMBC for cakes/cuppies, etc.

I also use the Italian Meringue buttercream. It comes out smooth, shiny and is very easy to work with!