[Ozban]

For my part, I read Aladrion and Erendis frequently. Deem it to be one of the best parts of all Tolkien's works. And then the whole of Quenta Silmarilion (if I were to chose, then the part from 'Of Eldamar and the Princes of the Eldalië' to 'Of the Sindar' is in my opinion the best, or I like to read it the most, quality is rather difficult category).
I should add Aindulindalë, but that limps after those two, I deem it unfinished, or rather unpolished (if such a thing ever can be). 'Scouring' and The Last Stage would come close after.