“If peanut butter cookies are made from peanut butter, what are Girl Scout cookies made out of?”

“If peanut butter cookies are made from peanut butter, then what are Girl Scout cookies made out of?” is a joke that has been included in many collections of one-line saying. “If peanut butter cookies are made from peanut butter, then what are Girl Scout cookies made out of?” has been cited in print since at least 1999.
 
A similar joke that was said in the movie The Addams Family (1991) is “Are they (Girl Scout cookies) made from real Girl Scouts?”
 
 
SUPER HART’S JOKE COLLECTION PAGE 18
This Page created on November 7, 1999!
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CARLINISMS FOR THE MILENNIUM
If peanut butter cookies are made from peanut butter, then what are Girl Scout cookies made out of?
   
Google Books
Net-Wit.Com:
A Smorgasbord of E-Mail and Internet Wit Blended With Humorous Incidents From the Author’s Wild and Woolly Life
By Marvin Rubinstein
Rockville, MD: Vinmar Press
2000
Pg. 73:
If peanut butter cookies are made from peanut butter, what are Girl Scout cookies made of?
   
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MoffHITZ Girl
1/24/00
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23)If peanut butter cookies are made from peanut butter, then what are Girl Scout cookies made out of?
 
30 March 2000, Daily Globe (Ironwood, MI), Porcupine Press, pg. 7 banner:
If peanut butter cookies are made from peanut butter, then what are Girl Scout Cookies made out of?
 
16 April 2000, Paris (TX) News, “Free Advice” by Albert Nichol, pg. 10C, col. 6:
If peanut butter cookies are made with real peanut butter, what are Girl Scout cookies made out of?
   
Google Books
The Land Where My American Mother Died—Palermo, Sicily
By Bennett Lear Fairorth
Lincoln, NE: iUniverse, Inc.
2003
Pg. 224:
“If peanut butter cookies are made from peanut butter, what are girl scout cookies made out of?”
 
Google Books
Jokes, Quotes, And Other Assorted Things
By Stephen Motway
Xlibris Corporation (Xlibiris.com)
2011
Pg. 328:
If peanut butter cookies are made from peanut butter, then what are Girl Scout cookies made out of?