While the flatbread-sauce-cheese version of pizza most likely originated in Naples, Italy can’t quite take credit for inventing pizza. “The broadest definition of pizza is a yeasted flatbread with ingredients baked into it. That had its origins with the Greeks,” Helstosky says. “There’s archaeological evidence of bread ovens and pictorial and visual evidence of what appears to flatbreads with spots on them. The ancient Greeks’ bread, called plakuntos, became a meal in and of itself.” Because Naples was founded as a Greek port city, the pizza that developed there may be part of the lineage of Greek flatbreads, but pizza had a history preceding its rise to popularity in Italy.

“People treat San Marzano tomatoes like it’s some name brand, but that wording on the cans means nothing,” Wiener says. “San Marzano is the name of a seed. You can grow it well or grow it poorly. Now, in the European Union, San Marzano is a protected mark that has to be grown in a predicted region. If you grow your tomato in that region, you can get DOP certification. Where people in America get confused is think they all San Marzanos are those special Italian kind. When you go out shopping for a San Marzano, there’s a good chance that’s a tomato from China that’s packaged in Italy. I tell people to go buy three cans of tomatoes and taste them side-by-side to see which you like the best, whether it says San Marzano or not. For me, Trader Joe’s canned plum tomato is usually the best one.”

*(More reading on why choosing USA tomatoes Matters) 

“It’s our assumption that pizza had its origins in Italy and hopped over to America sometime in the 20th century. Around 1945 is when pizza went global,” Helstosky says. “But there’s a belief that pizza became popular in the United States post WWII because troops came home from war and wanted it. But I wasn’t about to find that in my research.” Helstosky says some basic facts about the war contradict the returning-GI theory of pizza’s spread. “The invasion of Italy was a limited number of U.S. troops. There were more soldiers in England, France, and Western Europe. And at the time, pizza was still a regional dish confined mostly to Southern Italy and Naples, so not many would have seen it. Also, when troops would have arrived near the end of the war, Naples was destitute. Neapolitans had become so desperate, they actually emptied out the city’s aquarium and ate all the fish in it. So I doubt soldiers would have said after being there ‘I had this great food in Naples.’” 

When New York City mayor Bill DeBlasio was spotted eating his pie with a knife and fork, he was pilloried. But Pashman takes umbrage with the umbrage. “A politician eats the pizza with a fork and knife and then comedians mock the politician,” Pashman says. “If politicians got it all over their face or dripped sauce on their shirt, the comedians would make fun of them worse. I can’t blame a politician for being careful around a slice.” But it’s not just elected officials who need not refrain from cutlery. “I interviewed Patsy Grimaldi, the 80-year-old who is the last pizzamaker in America to train under someone who trained under Lombardi, our closest link to America’s original pizzeria,” Pashman says, “And he told me he will use a knife and fork when the slice is too hot to pick up. So by all means, be like Patsy and eat pizza with a knife in fork.” Wiener largely concurs. “When you’re mayor of New York, you shouldn’t eat it with a fork and knife,” he says. “But the whole point of pizza is that it’s casual and the moment you put rules to pizza you violate what it is and that’s just lame.”

Pizza purists may argue that fresh mozzarella made with the milk of a water buffalo is the superior cheese for your pie, but even a self-described traditionalist like Samson agrees that the best cheese to use depends on the style of pizza you’re making. “The part-skim mozzarella, those individually wrapped logs of cheese like you see in Brooklyn—that’s the cheese to use in a true New York-style pizza,” Samson says. “Mozzarella di Bufala has more water in it and so it would make a soupier pie. So you want to make a big New York pizza with drier cheese.”

“It comes up on my tours all the time, and people are surprised that pizza places we visit don’t use dough made that day,” Wiener says. “If I give them the option of having dough made that day and dough that’s a day or two old, they pick the one made today. It may seem obvious to some people to want the older dough, but people think fresher is better. Why you want that older dough is that the process of proofing is more than just the physical rising. You can let dough sit out all day and it will rise, but if you drop the temperature, and let the dough rise slowly, it allows time for fermentation, which really develops flavor.”

You can order pepperoni pizza—you just won’t get anything with meat on it. “There is no such thing as a pepperoni sausage in Italy. It doesn’t exist there,” Samson says. “If you were to order it in Italy, you’d get peperoni, which literally means bell peppers. Pepperoni is an American thing. It’s a mix and beef and pork that’s smoked and they don’t do that in Italy. You could salame piccante in Italy, which is a spicy pork sausage. That’s the closest you’d get to pepperoni. But really, they don’t do much smoked meat in Italy; it’s usually cured, fermented, and aged.”