Complex sentence: In this tome, Wallach wrote about his most famous role as Tuco in "The Good, the Bad and the Ugly", commenting that he did not realize he was going to be "blessed" with that title until he saw the film.
Split into simpler sentences: In this tome, Wallach talked about his most famous role as Tuco in "The Good, the Bad and the Ugly". He mentioned that he didn't realize he was going to be "blessed" with that title until he saw the film.