I read many pages from "Everything you want to know about Buttercream" but still need help!  I've used Sharon Zambito (Sugarshack)'s recipe for years with great success.  Even using the Aldi brand shortening and powdered sugar I had smooth as silk buttercream.  But not lately.  I've tried using Domino's Powdered Sugar and even found a store brand of shortening with 0.5g of transfat.  Still not successful.  Does anyone have suggestions.  I can't even smooth it out with a spatula.  It still looks and feels grainy.  It does crust but the overall look is just not nearly as nice.  Thanks for any suggestions.

The only brand of shortening, other than hi ratio, that I have been able to find in my area that still has the full 2.5 grams of transfat per serving is IGA brand.

Try mixing it for less time at a lower speed after adding all the ingredients.

Are you using milk in your recipe or whipping cream? I had the same problem a few weeks ago, I used milk in my recipe and it looked runny and grainy. I found a recipe that used whipping cream, and it came out so perfect! Every bite had the best taste!

I used Domino PS!

I beat my butter, sugar, and vanilla for 3 mins before adding 1 tablespoon of whipping cream, and then beat everything together for another minute or two.

Thanks for the responses.  I've been using coffee creamer dissolved in boiling water for the liquid in the recipe.  It has worked for years but not so well for the last two weeks.  I did try it using Domino PS and really could not see any improvement.  Guess I'll just have to go ahead and invest in Hi Ratio shortening.

Thanks again for the suggestions.