Are there any bakeries or delis in manhatten that still make or carry onion rolls? They do not seem to be around any more.
lots of old school bakeries in queens still make them and so do some of the grocery stores. ithink I have gotten them at stop and shop in maspbeth
also tomcat bakery makes a pull apart parkerhouse roll with carmelized almost burnt onions on top and poppy seeds that is a definite takeoff on the old school onion rolls but much better quality. they only sell wholesale so not sure who buys those from them and resells o try cheese of all nations on austin street in forest hills.
places like sullivan street bakery and amys may also offer a version of these, its worth a try and there are plenty of other fabulous breads and rolls to try like fennel raison at amy's and olive breads and twists.