Entry in progress—B.P.
 
Wikipedia: French onion dip
French onion dip or California dip is an American dip typically made with a base of sour cream and flavored with minced onion, and usually served with potato chips as chips and dip.
 
History
French onion dip, made of sour cream and instant onion soup, was created by an unknown French cook in Los Angeles in 1954. The recipe spread quickly and was printed in a local newspaper. The Lipton company promoted this mixture on the television show Arthur Godfrey’s Talent Scouts in 1955, and early on, it was known as “Lipton California Dip”, but soon simply as “California Dip”. A Lipton advertising campaign promoted it on television and in supermarkets. The recipe was added to the Lipton instant onion soup package in 1958.
(...)
The name “French onion dip” began to be used in the 1960s, and became more popular than “California dip” in the 1990s.
 
Google Books
The American Century Cookbook
By Jean Anderson
New York, NY: Clarkson Potter
1997
Pg. 24: 
California Dip
THIS MAY not be “the mother of all dips,” but it is surely America’s most beloved. The Lipton Company, whose dry onion soup mix is the basis of California Dip, doesn’t claim to have invented it.  That distinction belongs to an anonymous California cook, who blended sour cream with the soup mix back in 1954—two years after it hit the market. Word of the new dip spread through Los Angeles faster than a canyon fire, newspapers printed the recipe, onion soup mix sales soared, and Lipton executives, a continent away in New Jersey, were ecstgatic. They tracked down the recipe, perfected it, and beginning in 1958, printed it on every box of Lipton Recipe Secrets Onion Soup Mix (it’s still there).