From Wikopedia:
Mallomars [3] are produced seasonally at Nabisco. A circle of Graham cracker is covered with a puff of extruded marshmallow, then "enrobed" in dark chocolate, which forms a hard shell. Mallomars were introduced to the public in 1913. Because Mallomars melt easily in summer temperatures, they can become difficult to find during the summer: they are generally available from early October through April. Devoted eaters of the cookie have been known to stock up during winter months and keep them refrigerated over the summer. Seventy percent of all Mallomars sold are sold in metropolitan New York.
According to the box, Mallomars are made in Canada by Kraft Foods
Also, interesting facts:
In act one of The Odd Couple, Oscar Madison offers Felix Ungar some chocolate Mallomars while trying to cheer him up after Felix and his wife break up.
Mallomars are featured in a moment of the feature film When Harry Met Sally... (1989). A forlorn Harry watches TV on New Year's eve with a box of Mallomars, referring to them as "the greatest cookie of all time".
Mallomars add local color to Wally Lamb's coming-of-age novel She's Come Undone.
Mallomars are mentioned on an episode of The Simpsons. Ned Flanders, during his final breakdown, in which he personally and wickedly insults every major character on the show, turns to Clancy Wiggum, the town's obese, incompetent police chief, and informs him, "The last case you got to the bottom of was a case of Mallomars!"
Mallomars are mentioned briefly on Family Guy. Peter Griffin "sold his soul once in 1977 for Bee Gees tickets and then again in 1983 for half a Mallomar."
Mallomars are mentioned in at least one Seinfeld episode.
Mallomars are mentioned in at least two episodes of The Golden Girls. On one occasion, Blanche tells the other girls to just tell her their bad news so she can get hysterical and eat a box of Mallomars. In another episode, Rose interjects during a discussion on literature, mistaking Malamud for Mallomars.
In an episode of Roseanne, Roseanne Connor (Roseanne Barr) discovers a box of Mallomars as she is just beginning a diet. In a 1991 episode entitled "Home Ec" Roseanne takes Darlene's Home Ec class on an educational shopping trip to the supermarket and the patron ahead of them in the check-out line is buying vodka, mallomars and a TV Guide. "I'm thinking single, and staying that way" Roseanne comments to the girls in reference to the pathetic gentleman.
Mallomars are mentioned in The Sopranos episode, "Big Girls Don't Cry." Tony has arranged a secret meeting with Paulie, who asks "I do something wrong?" Tony replies, "Sunday, my house, box of Mallomars on the counter?
Mallomars appear briefly in the WB series Felicity episode "Todd Mulcahy: Part 1." Todd sends Felicity a care package filled with art supplies and Mallomars. Then, in "Todd Mulcahy: Part 2," Felicity tearfully finds comfort in a Mallomar after Todd gets hit by a speeding bus.
Mallomars appear in Gilmore Girls; Lorelai receives traditional birthday Mallomars every year from her daughter Rory. Also in one episode Rory pins a message for Lorelai to Mallomars because that way Lorelai is bound to find them. In another episode, Rory and Lorelai are seen eating Mallomars after Rory has a bad date.
Mallomars are mentioned in Regarding Henry, the 1991 movie staring Harrison Ford and Annette Bening. They were Henry's (Harrison Ford's character) favorite treat before he suffered from retrograde amnesia as a result of being shot multiple times.
Mallomars are shown during an episode of "The Nanny" when Fran comforts Maggie concerning a breakup.
Mallomars are mentioned during the Conan O'Brien skit "Pierre Bernard's Recliner of Rage", where Pierre complains about the inability to get Mallomars during the summer months.
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