When a recipe states “Add 8 cups of water,” it usually meals to add that to a bowl or to a pitcher. A “dumb blonde” joke about Jell-O was posted on the newsgroup rec.humor on September 12, 1991:
   
Q: Why don’t blondes eat Jell-O?
A: They can’t fit two cups of water in the little boxes.
 
A similar “dumb blonde” joke about Kool-Aid was published in The Tennessean (Nashville, TN) on October 13, 1991:
 
Q: Why don’t dumb blondes like to make Kool-Aid?
A: They can’t fit eight cups of water in that little package.
   
   
Wikipedia: Jell-O
Jell-O is a registered trademark of Kraft Foods for varieties of gelatin desserts, including fruit gels, puddings and no-bake cream pies.
     
Wikipedia: Kool-Aid
Kool-Aid brand flavored drink mix is owned by Kraft Foods. The product has been around since 1927, once the powder form was created by Edwin Perkins based upon a liquid concentrate called Fruit Smack.
           
Google Groups: rec.humor
BLONDE JOKE LIST!!!
Michele Zumbo
9/12/91
(...)
>Why don’t blondes eat Jell-O?
>They can’t fit two cups of water in the little boxes.
 
13 October 1991, The Tennessean (Nashville, TN), “Scene and Heard” by Catherine Darnell, pg. 1F, col. 5:
Why don’t dumb blondes like to make Kool-Aid?
They can’t fit eight cups of water in that little package.
 
Google Groups: alt.tasteless
Definitve list of blonde jokes
RichHalbs
10/16/91
(...)
2.  Why don’t blondes like making Kool-Aid?
Because they can’t fit 8 cups of water in the little packet.
 
Google Groups: hsv.general
joke of the week
Dave Luce
3/18/92
*********************
* DUMB BLONDE JOKES *
*********************
(...)
25. Why don’t blondes eat Jello?
A:  They can’t fit two cups of water in the little boxes
(...)
83. Why don’t blonde’s like to make Kool-Aid?
A:  They can’t fit 8 cups of water in that little package
     
Google Groups: rec.humor
Canonical List of Blonde Jokes (was Largest List of Blonde Jokes)
Belding, Troy C.
8/31/93
(...)
Q:  Why don’t blondes like making KOOL-AID?
A:  Because they can’t fit 8 cups of water in the little packet.
 
12 July 2001, Houston (TX) Chronicle, “Jokes 101: Did You Hear About…?” by Sherry Thomas, pg. Y1:
Why don’t sixth-graders make Kool-Aid?
They can’t fit 8 cups of water in the little packages.
 
Twitter
cnpsupport‏
@cnpsupport
Q: Why don’t blondes like making KOOL-AID?A: Because they can’t fit 8 cups of water in the little packet.  oooh another for Angelo 😊
9:40 PM - 3 May 2009
 
Twitter
leah carlson‏
@leahmary_23
@CortneyEarhart why cant a blonde make jello?? ... Cause she cant fit two cups of water in the little box #lol #mademethinkofyou #luvya
11:27 PM - 27 Jan 2013
   
Twitter
@TulchiGreen‏
@TulchiGreen
I never make cool-aid because I can’t figure out how to get 8 cups of water into the small packet!!
5:32 AM - 12 Feb 2017
 
Reddit—Clean Jokes
Why Don’t Blondes Like Making KOOL-AID? (self.cleanjokes)
submitted December 17, 2017 by marveluzu
they can’t fit 8 cups of water in the little jacket