Adapted from Martha Stewart's Cupcakes
Makes about 3 cups
Step 1: Beat cream cheese and confectioners' sugar with a mixer on medium speed.
Step 2: Add salt, then peanut butter, then vanilla.
Step 3: Whisk cream until soft peaks form, and then fold into peanut butter mixture.
Step 4: Use immediately, or cover and refrigerate for up to 2 days. Bring to room temperature, and beat on low speed until smooth before using.