Preparation - Fry the bacon until evenly browned. Drain, crumble, and set aside. Whisk together the mayonnaise, sour cream and Italian salad dressing mix; set aside. Tear the lettuce into bite size pieces. Wash and dry the torn lettuce in a salad spinner, then place it in a large salad bowl. Arrange the seeded and chopped tomatoes, crumbled bacon, and croutons over the lettuce. Pour the prepared dressing over top. Toss, then serve immediately.