Blue Moion is a Belgian-style witbier brewed by MillerCoors. The beer is usually served with an orange slice.
 
There are many “once in a Blue Moon” jokes. “I hardly ever eat orange slices. Maybe once in a Blue Moon” was posted on Twitter by Prerana Shrestha on August 7, 2011. “I rarely put orange slices in my beer. Once in a Blue Moon” was posted on Reddit—Dadjokes on January 19, 2020.
   
   
Wiktionary: once in a blue moon 
Adverb
once in a blue moon (not comparable)
1. (idiomatic) Very rarely; very infrequently.
 
Wikipedia: Blue Moon (beer)
Blue Moon Belgian White (branded as Belgian Moon in Canada) is a Belgian-style witbier brewed by MillerCoors under the name the Blue Moon Brewing Co. It was launched in 1995, and was originally brewed in Golden, Colorado.
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The grain bill for Blue Moon includes malted barley, white wheat, orange peel, coriander and oats—and is usually served with a slice of orange, which its brewmasters claim accentuates the flavor of the brew.
               
Twitter
Prerana Shrestha
@prerana123
QOTD2: ‘I hardly ever eat orange slices. Maybe once in a Blue Moon.’
10:27 PM · Aug 7, 2011·Twitter Web Client
   
Twitter
lowercase j
@jAREDkESSEL
I only eat Orange Slices once in a Blue Moon. (rimshot)
3:22 PM · Oct 2, 2012·Twitter Web Client
   
Twitter
Comment ça va? Do you Phil Gould?
@phool
“Do you ever eat orange slices?”
“Once, in a Blue Moon.”
9:34 PM · Apr 21, 2014·Twitter for Android
   
Twitter
harper
@harperb
“Do you ever put orange slices in your beer?”
“Once in a blue moon”
10:35 PM · Feb 9, 2015·Twitter for iPhone
   
Twitter
Bill Pangus
@PillieWinkham
How often do I have orange slices?
Once in a Blue Moon
5:51 PM · Jun 23, 2015·Twitter for Android
   
Twitter
New Year, New Pete
@GunsPete
Some people always put orange slices in their wheat beer, but I rarely do it. So far just once, in a Blue Moon.
2:41 PM · Nov 4, 2015·Twitter Web Client
   
Twitter
Funny Bot
@lAmFunnyBot
How often do I put orange slices in my beer?: Oh, once in a Blue Moon.
11:09 PM · May 6, 2017·Funny Bot - Reddit
 
Reddit—Dadjokes
Posted by u/hastings43 November 10, 2017
I don’t put an orange in my beer often
Except maybe once in a Blue Moon
 
Reddit—Jokes
Posted by u/GeezusManForReal March 24, 2018
I asked my buddy if he always puts an orange wedge in his beer.
He said, “Ehh not really. Maybe once in a Blue Moon.”
 
Reddit—Jokes
Posted by u/ElDon114 June 21, 2018
I don’t put orange in my beer very often
Except maybe once in a Blue Moon
 
Twitter
Jordan Ramsay
@DangOlWill
Do I like beer that they serve with a little orange slice in there? Sure, once in a blue moon
3:00 AM · Nov 28, 2018·Twitter for iPhone
   
Reddit—Dadjokes
Posted by u/Dan-Quixote March 9, 2019
Do I often put an orange slice in my beer?
Not really. Maybe once in a blue moon.
 
Twitter
Michael ‘Mankilla’ Miller
@thegirlmichael
Orange slices in beer?
I like it once in a Blue Moon.
10:08 AM · Sep 23, 2019·Twitter for Android
     
Reddit—Jokes
Posted by u/paraouji December 24, 2019
Bartender asks a man “You ever had ann orange in your beer?”
Man says “Once, in a Blue Moon.”
 
Reddit—Dadjokes
Posted by u/MelkorHimself January 19, 2020
I rarely put orange slices in my beer.
Once in a Blue Moon.