Jessica, your buttercream post left me curious about what went wrong, so I can avoid it. It also made me crave some peanut butter icing. Ian demanded a chocolate peanut butter cake before I left, and since I’m missing his birthday I felt he was probably entitled. Plus, it’s definitely my favorite icing and the one I’m most likely to make just to eat (although usually I don’t have enough cream cheese and just use sour cream or yogurt to add some tang).
My basic recipe (inspired by the one in Sky High) is usually 2 parts cream cheese to 1 part butter and then icing sugar and peanut butter to taste and consistency. This icing benefits from whipping before the peanut butter is added, but isn’t necessary if you’re just spreading it on apples or crackers.