I made a wedding cake 2 weeks ago and have quite a bit of buttercream icing left over. I have another wedding cake to do for a wedding this weekend and the bride-to-be would like carrot cake. Long story short, the reception will now be held outdoors, and I am concerned about using a cream cheese icing on the cake because it is supposed to be about ninety degrees this weekend. I was combing through this forum and found a recipe for Decorators Cream Cheese Icing which claims to hold up better than just cream cheese icing. The only difference between my buttercream icing recipe and the DCCI recipe is the cream cheese. My question is this: can I take my left over buttercream icing that I made a few weeks ago and just re-mix it and add the cream cheese to it? I hate to waste all that icing that I have now!