I haven't tried it, but I do think the Cool Whip, or regular whipping cream, would break down in no time. I suggest trying it with Pastry Pride non-dairy cream. It comes frozen; defrost in the fridge for a couple of days, then whip as usual. Add some vanilla for flavoring. My grocery store doesn't carry it, but Smart and Final does, and does Do It With Icing store in my town. Many someone else will have another suggestion for you.
I mix cool whip and cream cheese for a fruit dip, tastes pretty good, but yes, it will break down and melt. I've never tried it with icing.
Hi lsawyer! You're in my area!
actually, it should be ok. in my experience, cool whip holds up better than real whipped cream. i do a non crusting icing which is basically creamed cream cheese, vanilla, a small amount of powdered sugar , and fold in real whipped cream. it pipes well and holds up reasonably well- as long as you can refrigerate it, and keep it out of the summer heat. it wont crust- and make sure that you GENTLY FOLD the cool whip into it. DONT beat it with a mixer or it will certainly become a runny mess.
http://forum.cakecentral.com/cake_recipe-901-Whipped-Cream-Frosting.html
EDITED TO ADD RECIPE
http://www.cakecentral.com/cake_recipe-2231-Cream-Cheese-Icing.html
I am just about to use this one for a cake next weekend. Looks like you can decorate with it cause it has the crisco in it! Try this one!!
Hey! CakesByMonica!! where in San Diego?? I lived out there for 6 years and I loved it!! Can't wait to go back! 
http://www.cakecentral.com/cake_recipe-2231-Cream-Cheese-Icing.html
I am just about to use this one for a cake next weekend. Looks like you can decorate with it cause it has the crisco in it! Try this one!!
Hey! CakesByMonica!! where in San Diego?? I lived out there for 6 years and I loved it!! Can't wait to go back!
I live in La Mesa. I've been trying to find local CC'ers!
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