“Wonton egg drop soup” adds together wontons (as in wonton soup) and egg drop soup. It’s not known who first thought of the combination, but it began appearing on Chinese-American restaurant menus in the late 1980s and early 1990s.
 
“Wonton Egg Drop Soup” was printed in a Binghamton (NY) newspaper in 1989, an Easton (MD) newspaper in 1992, and several newspapers in 1993.
 
     
Wikipedia: Egg drop soup
Egg drop soup (traditional: 蛋花湯; pinyin: dànhuātāng; literally “egg flower soup”) is a Chinese soup of wispy beaten eggs in boiled chicken broth. Condiments such as black pepper or white pepper, and finely chopped scallions and tofu are optional, but commonly added to the soup. The soup is finished by adding a thin stream of beaten eggs to the boiling broth in the final moments of cooking, creating thin, silken strands or flakes of cooked egg that float in the soup. Egg drop soup using different recipes is known to be a simple-to-prepare soup in different East Asian and Western countries.
     
9 January 1989, Press & Sun-Bulletin (Binghamton, NY), pg. 6B, col. 4 ad:
(Tong’s Wok Kitchen, Endicott Plaza, Endicott, NY.—ed.)
Wonton Soup
Chicken Egg Drop Soup
(...)
Wonton Egg Drop Soup
 
28 May 1992, The Star-Democrat (Easton, MD), pg. 10A, col. 1 ad:
(Jin Jin, 6 North Washington Street, Easton, MD.—ed.)
Wonton Soup
Egg Drop Soup
Wonton Egg Drop Soup
 
17 March 1993, Dayton (OH) Daily News, pg. 8-Z7, col. 1 ad:
(Dragon King, 852 Union Boulevard, Englewood.—ed.)
Wonton Soup
Egg Drop Soup
(...)
Wonton Egg Drop Soup
 
9 April 1993, Newsday (Long Island, NY), “Eats” by Joan Reminick, pg. 75;
(Imperial Orchid; 724 Deer Park Avenue, Babylon.—ed.)
Wonton soup ($1.55) was fine, if nonspectacular, as was the mixed wonton / egg-drop soup ($1.75).
 
4 May 1993, St. Albans (VT) Messenger, pg. 13, col. 3 ad:
(China Wok Chinese Restaurant, 139 North Main Street, St. Albans, VT.—ed.)
Wonton Soup
Egg Drop Soup
(...)
Wonton Egg Drop Soup
     
15 January 1998, St. Petersburg (FL) Times, “The line on Hong Kong Buffett” by Jim DeBrosse, pg. 3D:
(Hong Kong Buffet 890 Third Avenue South, St. Petersburg.—ed.)
The wonton egg drop soup ($2.50) was fresh, not too salty and loaded with tender egg white and plump, delicately sliced wontons.
     
4 January 2002, Philadelphia (PA) Inquirer, “Chinese place in Maple Shade has 142 choices, by actual count,” pg. W32:
(Great Taste, Kingsway Plaza Shopping Center, Kings Highway and Lenola Road, Maple Shade.—ed.)
From the list of 142 choices (Li’l Dep counted ‘em), the family chose a pint of chicken with crispy snow peas ($4.05); shrimp with Chinese veggies (gotta love that baby corn) for $4.70; a pint of wonton egg drop soup ($1.25); and some crisp spring rolls ($1.25 each).
     
16 May 2003, Orlando (FL) Sentinel, “A Nice Wok in the Park” by Joseph Scott, pg. 50:
(Mein Street Wok, 3837 Avalon Park East Boulevard, Orlando.—ed.)
If you’re like me, you always have a hard time trying to decide if you’re in the mood for egg drop soup or wonton soup. If you spend an inordinate amount of time trying to decide, then you’re nothing like me and you should probably seek help.
 
But Mein Street Wok has solved the problem—the one about the soup, not your obsessive-compulsive disorder—with a wonton egg drop soup. The best of both worlds. So I not only had the feathery texture of egg in the hot broth, but also a big pasta pillow with a pork filling.
   
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@LolicOnion
Should I get wonton soup or egg drop soup or wonton egg drop soup?
7:53 PM - 27 Nov 2016
 
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Kitchen Concoctions
@KitConcoctions
{NEW!} Skip the take out tonight and make your own Wonton Egg Drop Soup with a few simple ingredients! {ad} #BibigoKoreanFlavor #RecipeOfTheDay Recipe Here -> http://bit.ly/KCweggds
2:19 PM - 17 Aug 2018