Ethiopian was one of the cuisines I thought of after seeing the thread title, before reading the alt-text. Thought, "nah, that's probably common enough these days", but then again, I can only actually think of one Ethiopian restaurant in my hometown. I've been there, and it was pretty delicious. I don't remember exactly what I got way back then, but I do recall the injera. I dunno; I thought it was pretty delicious the first time I tried it, and wouldn't have considered it an acquired taste. Although it could be that my culinary background disposed me to it, or perhaps it was different than what you had while actually in East Africa.
I've found that Swedish cuisine is not particularly well known on the west side of the Atlantic. To an extent, it does share a lot of common base ingredients with German cuisine - meat, potatoes, and fish, in particular. It's hard to go wrong with any of several Swedish meatball dishes, or
gravad lax (the latter of which is sold at one place locally). Moving into the less often found are moose and reindeer meat dishes. According to Wikipedia, Swedes hunt twice as many moose as North Americans... which seems entirely plausible given how common moose dishes are. And good luck finding reindeer in North America where they pull Santa's sleigh! Amongst vegetables,
cloudberries are pretty common in Sweden, but I've yet to see them in North America. They're commonly used on
Swedish pancakes and ice cream, particularly in the form of jam.
Amongst beverages and dessert,
julmust is a soda that outsells Coca-Cola in December, and can be found in multiple varieties across the pond as well.
Akvavit and
punsch are common alcholic beverages that, while tasty, are generally difficult to find overseas (I've found Danish and Norwegian akvavit, but they aren't the same... Norwegian is closer). And of course, there's the Swedish pastries. I was disappointed to find IKEA was sold out of
dammsugare, a delicious pastry whose name means "vacuum cleaners", when I was last there. And while IKEA did had cinnamon rolls, they were Americanized, more of a cross between Swedish and American ones than true Swedish ones.
I think the "weirdest" thing I've had is Sushi. It was pretty great, actually. Tuna, I think it was, with a strong Wasabi taste. Man, Wasabi is so much better than Jalapeno and Habanero. I should have more Sushi.
Now I feel sad that I haven't tried Shawarma.
I don't think sushi really qualifies as lesser-known cuisine these days. Especially with tuna and other such fish, or eel for that matter. Slightly more exotic sushi - octopus, fish roe, or sea urchin - might qualify as less common. I had an urgin' to try urchin the last time I had sushi, but the restaurant no longer carried it. Oh well.