Mallomars turn 100 today.
What's a Mallomar you might ask? The slightly elusive chocolate-covered marshmallows with a graham cracker cookie base are only packaged and sold during the autumn and spring – from September to March, according to National Public Radio.
That's because the warm weather would have melted the cookies' chocolate coating back when Nabisco first sold them to a Hoboken, N.J., grocer on Nov. 13, 1913.
But despite advances in refrigeration, a brand spokesman told NPR the cookies are only sold during the select months to maintain tradition.
And most of Mallomars are found in the Northeast, where 95 percent of them are sold, often found stowed away in someone's freezer.
The cookies have somewhat of a pop culture mystique about them – what the company that sells them calls a nostalgic brand.
As part of their 100th birthday, the company is running a "Mallo-Memories" sweepstakes on its Facebook page where people reminisce about their best Mallomar stories.
Even fictional mob boss Tony Soprano threatens a member of his crime family for stealing his box of Mallomars. Of course, he was kidding.
And Billy Chrystal's character in the beloved 1989 romantic comedy "When Harry Met Sally" declared the marshmallow cookies "the greatest cookie of all time," according to The Jersey Journal.