TRAVELING in the United States, one often encounters food proudly touted as authentically “New York,” including pizza, hot dogs, cheesecake, Manhattan clam chowder, pastrami and loaves of rye. Sadly, such honorifics almost always prompt invidious comparison, resulting in a good laugh if not a few homesick tears.


I still recall biting into a bialy about 15 years ago at the Broadway Deli, a favorite in Santa Monica, Calif., that closed in 2010. I was doing research on that scrunchy, savory Jewish-Polish onion roll. Identified as a “New York bialy,” its rubbery, pale appearance was fair warning. It came as no surprise that what looked like a white Rubbermaid sink stopper would taste like one, too.


Similarly, I have never met an out-of-town New York bagel that was not huge, puffy, soft-crusted, slightly sweet and lacking a sharply defined hole. New York cheesecake away from home is usually closer to the all-American Sara Lee model: thin and creamy, often with flavors that deviate from the traditional vanilla or lemon rind.


Even more depressing, though, is the difficulty of finding what I consider authentic examples of these foods at home in New York. Economics, technology and altered sensibilities have brought changes, and the foods that I cherished from the 1930s to the mid ’50s are (like myself) not quite what they used to be.


Hence this search for true New York classics. Better is not the issue; this is about lost tastes. Nor is this an attempt to find new variations on old favorites. Rather, it’s a search for foods that recall my original ideals.


PIZZA


Forget Naples for now. The goal is New York City pizza margherita with a thick, crackling hot and blistered rim of yeasty dough, mantled with thickish tomato sauce and decked with slim ribbons or dicings of slightly dry domestic cow’s milk mozzarella, all of it graced with grated Parmesan. Scorched in a coal-fired brick oven, the pizza emerges meltingly stringy with an inner crust that is thinner than the rim, but crisply substantial enough to hold as the triangular slice is folded and lifted to the mouth, with oregano and dried chiles to be sprinkled on.


The pizza that almost always still meets those standards is at John’s of Bleecker Street. Good news for those needing pizza by the slice is the recent return of Mario DiRienzo, the original proprietor of Famous Ray’s Pizza in Greenwich Village. He has renamed the same location Famous Roio’s Pizza in honor of his Abruzzo hometown, Roio del Sangro, and the huge slices are deliciously New York.


CHEESECAKE


The New York classic is high and light but subtly textured, with a pale yellow blend of cream cheese, sometimes with a little pot cheese or sour cream, and always lots of eggs, sugar and vanilla. Grated lemon rind is the only other acceptable flavoring. The cake might be based on a thin cookielike crust or one formed of crushed graham crackers. The best example from the old school remains S & S Cheesecake, which has a delicate cookie crust and a good belt of natural vanilla. It is baked on 238th Street in the Bronx and can be ordered and then picked up fresh, warm and unfrozen. It is also sold online and at Zabar’s and two Dean & DeLuca stores, but is shipped frozen, a process that does not overly mar the texture but leaves the cake just a bit sunken when not gently thawed.


A close second is Junior’s famed cheesecake, but only at the original restaurant in Downtown Brooklyn. Portions there seem fresher, lighter and more evenly moist, and with a nicely caramelized flavor, in contrast to some at the Grand Central Terminal outpost, where they can be a bit chewy and slightly soggy. Either way, avoid any hint of fruit or its sauce anywhere near the cake.


MANHATTAN CLAM CHOWDER


For complete accuracy, this perhaps should be called Brooklyn-Manhattan clam chowder, as my benchmark is the version I remember from the original Lundy’s restaurant in Sheepshead Bay. Most typically, it is a clear tomato-based vegetable soup with dicings of carrots, celery, onions and potatoes, along with tangles of clams — some in shreds, others in plump belly chunks — all enhanced by a heady belt of thyme, the seasoning that underpins the saline bite of the clams. Manhattan clam chowder is still widely available at Greek coffee shops on Fridays, but most are canned, overly thick and starchy versions. Otherwise it is hard to find in restaurants, where the creamy New England chowder somehow prevails.


But a few, like the Grand Central Oyster Bar and Restaurant, BLT Fish in Chelsea and Aquagrill in SoHo, regularly serve the hometown soup. The Oyster Bar’s chowder is pinkish with a cornstarch thickening and has the gentle flavor of thyme, oregano and bay leaves, and only mild clam undertones. BLT’s version, alas, is overpowered by smoky bacon. Aquagrill ladles out the classiest, headiest Manhattan chowder, redolent of sea breezes, with fresh clam bits. The most generous amount of clams in recognizable belly pieces, along with shreds, is at Randazzo’s Clam Bar in Sheepshead Bay. It is a thick sauce of a soup without any refinement, but with a very filling zap. Detecting no thyme, I asked if it contained any. “I don’t know,” the waitress answered. “I’ve never tasted thyme.”


BAGELS


I remember them well. Say, about three and a half inches across with a good wide center hole; a crisp, shiny, golden crust; and chewy, dense, gray interiors that turned to stone if not eaten within three hours of being baked. (A few words about the hole: It is essential first because it ensures a crisp crust at the center, and because the cream cheese and smoked salmon, when properly laid across that empty expanse, afford a luscious mouthful uncompromised by bread.) Their like will not come this way again, given shortages of skilled workers and the modern taste for softness and eternal shelf life, plus the need for a gigantic size to justify a retail price that covers the high cost of labor.