That’s bullshit. You learned it from the “Life in the 1500s” email hoax or from a site that repeated its claims.
In fact,
Soybeans are not native to North America, but they certainly are growing well and are in everything, and in the last few years they have become eaten more by them selves instead of just processed and added as an ingredient.
Anyone who thinks vanilla is plain should be sentenced to live a year without vanilla in anything.
The French were among the last Europeans to adopt the potato. The French peasants resisted every attempt to get them to farm it. It wasn’t until times got really rough in the late 1700’s and their wheat, rye, and other above ground foods got trampled or looted by passing armies that they saw the virtue of an underground tuber. Once they started eating the potato, its culinary appeal was obvious.
Potato (Blackadder)
Yes, chiles are a New World crop. More info here.
Chiles & many other interesting plants–from the New World & the Old–are members of the family Solanaceae. Some of these plants are toxic (or even hallucinogenic). Even the agriculturally important plants have toxic bits; don’t make tea from potato or tomato leaves!
If by “perfected” you mean “eliminated the entire point of eating onions in the first place”. Why would anyone want an onion that doesn’t taste like onion?
Tacos in the United States. Believe it or not there was a point where those living far from the border would have had no idea what a taco was. Taco, is that Greek? I know I don’t even think of tacos as being a foreign food these days.
I remember my stepfather’s parents visiting us in the mid 1970’s in Los Angeles and they had never heard of a taco. They weren’t from Hicksville either. They lived in Chicago.
Make up your mind.
How about the doner kebab in Germany or chicken tikka masala in the UK? Both are local adaptations of foreign foods that are extremely popular in those countries.
I laughed until I realized, I’m from St. Louis.
Wow, thanks so much for the replies y’all. This is such fascinating reading! I had no idea about the coffee, tomatoes (I think I knew that one but forgot), or potatoes (again prolly once knew and forgot).
I think the most interesting to me is the new world-old world movement, because for those things we can actually pinpoint an approximate time when one people started using them.
Also, no idea that chiles were from Mexico. Cannot imagine Indian food w/o them.
Kiwi fruit, once native only in China and called the Chinese gooseberry, i ow a US grocery staple.
Gestalt, food history is now a standard academic field:
You might want to get a introductory book on the subject and read about how various foods how traveled around the world. Unfortunately I don’t know of a good introduction to the subject. Can someone suggest one?
[quote=“Chimera, post:10, topic:556633”]
Do you suppose that they had Tisanes in Europe before they had black tea? I always presumed that they must have something other than brandy which they drank warm!
Ditto for Italian. But having eaten both the “authentic” form from family dinners and the “inauthentic” Chicago born nitrate laden variety, give me the Olive Garden any day of the week! 
In the small Scandinavian-American community where I was raised all of social life revolved around having coffee together. It was such a wake-up moment the day it occurred to me that coffee wasn’t indiginous to the Scandinavian countries.
To this day common Scandinavian cookery has very little use for spice other than cardamom, nutmeg and cinnamon.
When I was a child occasionally we’d go into a grocery store which had coconuts or fresh pineapple and that was a real novelty. Even fruit out of season was unheard of.
I have several, as this is an interest of mine.
Food In History - Reay Tannahill
Spice: The History of a Temptation - Jack Turner
Nathaniel’s Nutmeg - Giles Milton
An Edible History of Humanity - Tom Standage
And the classics: Salt, Cod, and The Big Oyster by Mark Kurlansky.
And, after they were done with that, they put it into their cuisine.
Those baby corn-cobs you sometimes see in Chinese dishes could not have been there before Columbus, maize being a New World crop. The mystery is why the Chinese don’t seem to use full-grown maize for anything, except maybe kernels in fried rice.
Or, maybe they do – I’m judging Chinese cuisine here by what’s on the menu in “Chinese” restaurants in the U.S.