For The Soup: In a 4-quart non-reactive pot over low heat, melt the butter. Add the leeks, thyme and bay leaves; cook, covered, for 20 minutes, stirring once or twice. Stir in the tomatoes, stock, sugar, salt and pepper. Bring to a simmer, then cook, uncovered, stirring once or twice, for 25 minutes, until the tomatoes are very tender and the soup has thickened. Cool slightly, remove the bay leaves, and force the soup through the medium blade of a food mill (or puree in a food processor). Transfer to a bowl, cover and refrigerate until cold, at least 5 hours. The soup can be prepared to this point up to 2 days ahead. For The Black Olive Cream: In a small bowl whisk together the black olive puree and the cream. To Assemble: Taste the soup and adjust the seasoning. Ladle into chilled bowls and drizzle the puree over each serving. Sprinkle with diced red tomatoes if desired and serve immediately. From "Cooking for the Weekend" by Michael McLaughlin. From the Chicago Tribune 7/1/93.