Please tell me how New England Clam Chowder is different from Boston Clam Chowder, as well as what Authentic Clam Chowder is?
If you want to go through the whole alphabet, you can start with
"Authentic Clam Chowder" and work you way to "Zesty, Low-Carb, Providence-style Razor Clam Chowder with Prosciutto, Roasted Hubbard Squash and Sunflower Seeds, Topped with a Dollop of Beet Foam."
OK, we made the second one up. Actually, while there are practically an infinite number of clam chowders, there are very few widely accepted names for them and none are “official.”
First, there is no Authentic Clam Chowder. Jasper White, building on the research of others, offers a concise history of chowder from the first written reference in 1750 to the present in his great little book, 50 Chowders (Canada, UK).
It is unclear if chowder was an invention of the French, British, or Native Americans, but its development clearly has links to the growth of the fishing trade off the coast of the Canadian Maritime Provinces and New England. Fish chowder received its first bit of publicity in 1751 in Boston, while there was no written reference to clams in chowder until 1833, when Lydia Maria Child mentioned that “a few clams are a pleasant addition” to her fish chowder recipe. (While it makes many New Englanders squirm, Ms. Child also used the same recipe to introduce the concept of adding tomato (in the form of ketchup) to her chowder instantly igniting the issue that has forever sundered sensible New Englanders and their milk-based New England Clam Chowder from their big-city neighbors to the south with their tomato-mish-mash Manhattan Clam Chowder. Will these senseless feuds never end?)
Anyway, in 1837, another cookbook writer, Eliza Leslie, took the courageous stand that “chowder may be made of clams,” and further secured the world’s gratitude by advocating the use of potatoes in chowder. In decades to follow, thousands of varieties of clam chowder evolved, often according to ingredient availability (soft-shell clams, or steamers, being the staple in Maine because of their abundance; quahogs being chosen on Cape Cod because of their profusion).
Among thousands of clam chowders, no more than three or four broad categories have taken on names that chefs or food snobs would agree on. There are two recognized types of New England clam chowder (the assertive chowder made with quahogs and seasoned with herbs and often garlic, and the sweeter, more subtle steamer, or soft-shell, clam chowder, which is less
heavily seasoned). According to Jasper White, both include a creamy broth with clams, potatoes, onions, celery, and salt pork or bacon, but neither of these two varieties has an official name other than New England Clam Chowder.
Yes, there is Manhattan Clam Chowder, which some have characterized as vegetable soup with clams. It, too, has many, many varieties. In between geographically and culinarily there is is Rhode Island Clam Chowder, which has neither tomatoes nor milk, but a clear broth (although pitchers of hot milk are often served alongside for those who realize that Rhode Island is actually a part of New England).
In your zeal to understand chowder, you have fallen into the trap of believing that like most things in our commercial society everything in the food world is branded. There is no official Boston Clam Chowder, nor can we find any agreement about what particular variation of New England Clam Chowder it would refer to. That doesn’t mean, of course, that dishes by that name don’t appear on hundreds of restaurant menus inside and outside of Boston. Authentic Clam Chowder is either an oxymoron or it applies equally to any and all clam chowders ever made.