Food is a very subjective thing; what's considered a delicacy in one place may be looked at with horror in another. After all, while most Americans would shy away from cubes of congealed pork blood swimming in soup, most Asians think cheese is disgusting.
There are some foods, however, that are so, um, “special” that even their cultures don't eat them very often. Below are five food that could be used as coming-of-age tests. I have personally consumed all five of these dishes; any hair that grows on my chest is directly attributable to these foods.
Also, notice that three of the five of these are Scandinavian, proof positive that living in a climate where the sun disappears for weeks at a time has made my people very, very desperate and very, very tenacious. The food of poverty, or hazing? You decide.
1. Casu marzu
Aged cheese is good. Extremely aged cheese can be an acquired taste, though the stinky-cheese partisans are a vocal and proselytizing group. Casu marzu, though, is its own level of horror. It's a Sardinian pecorino–sheep's milk cheese–that has been allowed to age so thoroughly that it contains live maggots. Whether you pick the maggots out or eat them is a matter of personal preference–but whatever you do, you chase it with either the biggest, strongest red wine you can find, or grappa.
The Norwegians are famous for their cod; even the bacalao that feeds the southwestern quadrant of Europe is made from Norwegian cod that's been splayed out, salted, and dried until it resembles a fishy billy club. Leave it to the Norwegians, though, to then reconstitute the fish with lye, and then soak the lye out of the fish, leaving a translucent, gelatinous blob of protein that smells like a janitor's closet. In fairness, Norwegians don't eat lutefisk nearly as often as Norwegian-Americans do, which just goes to show that winter in Minnesota is enough to drive otherwise normal people to strange lengths.
Surströmming, which means “sour herring”, is a Swedish dish of canned fermented herring. This is already bad enough, but the dish doesn't stop fermenting in the can, which makes the cans bulge in a way that would make even the hardiest, most intrepid foodie stop and think the word “botulism”. Cans have to be opened outside, because occasionally they explode, sending putrefied fish shrapnel toward anything unlucky enough to be within the blast radius.
Pulque is the native beer of Mexico, made from fermented aguamiel (the juice of the maguey plant). Though this was the tipple of choice for hundreds of years, it died off in popularity, perhaps because it tastes so horrendous. It's experiencing a hipster-driven, post-Aztec comeback, and is now even being sold in cans (though the contents are apparently even more disgusting than the fresh product). The problem with pulque isn't the ultra-strong kombucha flavor; it's the texture. Pulque has a slightly gelatinous texture that makes it seem like you're swallowing fermented snot. It's amazing that the same plant can produce pulque and its delicious distilled second cousin, mezcal.
Pulque is so strong-tasting that it often has fruit syrups (or just plain fruit) added to it to mask the taste; this is called pulque curado and can help you bridge the distance between looking like a wet little boy who can only drink a quarter liter before your eyes start to water, and looking like a hardened son of Mayahuel who can polish it off by the liter jug and then go off and fight.
Hákarl, pronounced “HOW-carl”, is Greenland shark that's been fermented–which is to say putrefied under control–and then dried. It's commonly sold in Iceland, though it reaches peak consumption during Þorrablót, the midwinter feast that features all kinds of dark-of-the-night, preserved food. The only possible way to consume this is to chase it with huge swigs of brennivín–schnaps–which just makes it more likely you'll lose your inhibition and eat more.