My absolute favorite is banana peppers and onions.. but bacon (REAL bacon, not Canadian bacon) and onion is a close second especially from Ginos in Toledo. Have yet to find anyplace here that comes close! In fact most Texas pizza places don't have bacon or banana peppers <sigh>... jalapenos are not the same.
All this pizza talk is making me crave a chipati (anyone from UM here? Pizza House in Ann Arbor ring a bell?