...is like savoring a quality piece of literature, such as Anna Karenina. As you chocolate lovers know, one cannot rush through a piece of dark chocolate, otherwise you miss the fullness of the texture and the flavor(s). You must let it melt in your mouth. It is the same with this book, which Tolstoy named his first novel. I highly recommend this marvelous literary work, even if you are not going to read anything else Tolstoy has written (quite a bold statement on my part, because I have not read any of his other works). The plot is very well developed, the characters are rich, and the moral dilemmas which Tolstoy addresses are timeless. Since Anna Karenina is about 800 pages, I would indeed recommend savoring it. It is well worth your time.
***EDIT*** I usually don't give full-blown synopses of books I'm reading unless I am addressing critical issues (in this case, there would be the numerous moral questions, as well as literary criticism) in it as well. I will recommend a book, and leave it up to you to look up. But here's a very succinct glimpse of the book to whet your appetite: a peek into the lives of 19th century Russian socialites and those who surround them.
By the way, I compare mediocre literature to milk chocolate. Too many added fillers, and not enough substance.