Voted for Chesterton, though the only author on the list that I have ever read is Waugh (though I liked what I read of him).
I do like Chesterton, but the vote was kind of a proxy vote for Gene Wolfe (he has written at least two explicit tribute stories to GK Chesterton). I have been consistently amazed by the work of Gene Wolfe. Even his mediocre stuff is better than most authors. I love how many of his stories seem to be religion-neutral or even anti-Christian, but are revealed to be profoundly Christian as the story unfolds. It strikes me as a great way to write about faith, since the truest nature of our world often does seem to be hidden from sight.
His highest regarded work is the solar cycle, but since that is 12 books long (The Shadow of the Torturer, The Claw of the Conciliator, The Sword of the Lictor, The Citadel of the Autarch, The Urth of the New Sun, Nightside the Long Sun, Lake of the Long Sun, Caldé of the Long Sun, Exodus from the Long Sun, On Blue's Waters, In Green's Jungles, Return to the Whorl) it probably is not the best for the new reader. (It is actually three separate related works, so it is possible to start at the Shadow of the Torturer or at Nightside the Long Sun). A better start is the novel Pirate Freedom which just so happens to star a Catholic priest. Who used to be a pirate.
Of course, I also am quite fond of JRR Tolkien. I have recently started to get into the stories of the First and Second ages. I am also currently rereading The Lord of the Rings and I am amazed by how many references there are to these earlier stories. But I guess it is to Tolkien's credit as an author that knowledge of the history of the world is not necessary to enjoy the story.