I've made countless frostings based on several ingredients (egg whites, cream cheese, butter..) but i can NEVER seem to get it to stay stiff enough to frost the cupcakes (yes they're cooled) and have it stay the way i did it.

what i'm talking about it putting the frosting in a pastry bag and using it to make a "typical" cupcake topper.



I follow the recipes to the letter now to make sure i'm doing everything right and it's still not working. help!

How long are you mixing the frosting?

Maybe add more powdered sugar. If mine isn't stiff enough, I add powdered sugar and that helps.

What about your butter? Is it too soft? Leave it out for a bit but you don't want it to be too soft.

hmm noted..my kitchen gets really hot when i bake so the butter might be past the "acceptable" point by then...i'm reluctant to add powdered sugar cause i find it makes my frosting taste funny if i add too much. but thanks for the advice!

I can't address recipes that use egg whites, but if it is a shortening/butter/powdered sugar icing, if it is too soft you either need less liquid or more powdered sugar. The amount can vary depending on humidity, temp, etc.

i usually only mix for about 30 seconds..or until it's all just blended. should i do it more?

More

Mix longer, add less liquid and more powdered sugar. For American buttercream, that's pretty much the only way to fix this problem.
If you don't want to add more PS, then start with putting in less liquid than the recipe calls for. I never follow a specific recipe for American buttercream, and just add liquid and PS until I get the consistency I want.
If you're making SMBC, you might not be getting your egg whites and sugar to stiff enough peaks before adding the butter...or might not be whipping it enough once the butter has been added.

I often let my butter get very soft, I have found that the sugar mixes better that way. Just me. But I also mix for a long time. I read on this site that if you add your sugar in small increments, beat longer it will take that twang taste away.

When I can't seem to get it right and all the p sugar in the world doesn't help I add one of two things. Either a bit of all purpose flour or cream of tartar.

Either one will help thicken your icing without changing the taste and will help with the crusting.

HTH

In most applications, butter performs best between 65˚F and 75˚F (18˚C and 23˚C), often referred to as "room temperature."

If you're making SMBC, here's a good tutorial.

http://fromscratchsf.wordpress.com/2011/08/02/more-about-swiss-meringue-buttercream-like-my-other-post-wasnt-long-enough-i-had-to-go-write-another-epic-post/

http://fromscratchsf.wordpress.com/2011/03/08/tutorial-swiss-meringue-buttercream/

thanks guys!