I came up with this one for a midsummer dinner party in very warm weather. I was thinking about a cold gazpacho, but while shopping, I saw some nice avocados and thought, Why not? This is more than just watery guacamole. You need to puree the avocado, which you shouldn’t for guacamole. Also, although you want to serve the soup cold, chilling avocados for any length of time causes them to turn very dark. So you must make the soup right before serving. And while I won’t even try to make guaca