If you are not serving the chowder within the hour, let it cool a bit, then refrigerate; cover the chowder AFTER it has chilled completely. Otherwise, let it sit at room temperature for up to an hour, allowing the flavors to meld. When ready to serve, reheat the chowder over low heat; don't let it boil. Ladle into cups or bowls and sprinkle with the chopped chives. Leave out the bacon and use vegetable stock to make this chowder vegetarian.