“You’re so dumb, you think Taco Bell is a Mexican phone company” (joke)

An old joke tells of a person who is so dumb (or stupid) that he or she thinks Taco Bell is a Mexican phone company. “And if you believe that, you probably also think Taco Bell is a Mexican telephone company” was cited in print in a newspaper on September 16, 1980. The joke was very popular during the 1980s. In the 1990s, the joke was used in a “yo’ momma’s so dumb/stupid” snap.
   
The largest Mexican telecommunications company is called Telmex.
 
   
Wikipedia: Taco Bell
Taco Bell is an American chain of fast-food restaurants based in Irvine, California. A subsidiary of Yum! Brands, Inc., they serve a variety of Tex-Mex foods including tacos, burritos, quesadillas, nachos, other specialty items, and a variety of “Value menu” items. Taco Bell serves more than 2 billion customers each year in more than 5,800 restaurants in the U.S., more than 80 percent of which are owned and operated by independent franchisees.
 
Google News Archive
16 September 1980, The Post (West Palm Beach, FL), pg. B7, col. 3:
And if you believe that, you probably also think Taco Bell is a Mexican telephone company.
 
20 September 1980, Iola (KS) Register, “At the Week’s end” by Bob Johnson, pg. 1, col. 1:
Laverne and Shirley—(...) Their two crazy sidekicks are Lenny and Squiggy (Joe Herder and Danny Johnson), who thought Taco Bell was a Mexican telephone company.
 
Google News Archive
5 July 1981, Daytona Beach (FL) Sunday News-Journal, “More ‘Juicy Tidbits’ About Roast Fall From Notebook” by John Carter, pg. 1B, cols. 3-4:
“To think all that came from Bert Reames, a man who thinks that Taco Bell is the Mexican phone company.”
 
29 April 1984, Los Angeles (CA) Times, “The Comedy Column” by Lawrence Christon, Calendar, pg. M86:
Rick Podel tells us, “A lot of people think Taco Bell is the Mexican phone company. Not true.”
 
14 October 1984, “Frank Gregory’s Talk of the Town,” Kokomo (IN) Tribune, pg. 19, col. 5:
George Newton thinks Taco Bell is the Mexican phone company.
 
5 June 1986, Aberdeen (SD) American News, Out & About, pg. 6B, col. 5:
WENDELL TROGDON, Indianapolis News columnist: “Uncle Clem doesn’t get out much anymore. Until this week, he thought Taco Bell was a Mexican phone company.”
 
4 November 1990, Daily News of Los Angeles (Los Angeles, CA), “THe years roll on, but Chi Chi laughs all the way to bank”:
Chi Chi Rodriguez is the only professional golfer I know who, upon approaching the green, will turn to the people standing there and loudly say, ‘‘HELLO!” This is just in case you might have failed to notice he is in the neighborhood, a highly unlikely possibility.” Did you hear about the new Mexican phone company?” Rodriguez says, apropos of nothing and to no one in particular. “It’s called Taco Bell.”
 
Google Groups: rec.humor
Insults
Nathan Mates
2/15/93
(...)
You so stupid you probably think Taco Bell is where you pay your telephone bill.
 
Google Books
Snaps:
The Original Yo’ Mama Joke Book
By James Percelay, Monteria Ivey and Stephan Dweck
New York, NY: Morrow
1994
Pg. 57:
You’re so dumb, you think Taco Bell is a Mexican phone company.