What is it?
Do you mean lutefisk?
From here:
I’ve never tried it but I know it’s huge in Minnesota in December.
Haj
Lutefisk is cod soaked in lye. It originated in Norway and is also found in the upper Midwest.
Here’s the recipe from the Sons of Norway.
Here’s a great story about the stuff.
What is lutefisk?
Lutefisk is gross.
Or perhaps a more politically correct answer…it’s an acquired taste.
blech.
Also known as bacalau in the Portugese and Philippine cultures.
Lutefisk is big attraction at the Norsk Hostfest . Trust me, I’ve been there. I’ve seen it. . . A lot of the attendees love it. Apparently, the King of Norway loved it when he was out here, too.
Tripler
Hostfest: too many old folk to count.
I agree wholehartedly. This from someone who likes haggis and sushi.
Tried it once, “once” being the opperative word.
If they somehow find any of it in Iraq they can count it as a bioweopon.
I saw lutefusk mentioned in “Drop Dead Gorgeous.”
I thought it was a joke until I asked a friend from Minnesota about it.
Ludafisk is that hot new Norwegian rapper from St. Paul. He wears a 5-pound necklace with a large golden fish pendant, and he sports a walleye lure hooked through his pierced eyebrow. He’s da bomb, ya know. 
Once upon a time, a Minnesota man (not of Norwegian heritage) discovered skunks living under his house. After smoke bombs, loud noises, and hounds had failed to remove them, a neighbor suggested that he throw two pounds of lutefisk under the house and leave for two weeks.
Desperate, the man dispensed two pounds of finely divided lutefisk under his house, and went on vacation for two weeks. When he returned, the skunks were gone, and he immediately went to thank his neighbor.
"Ole, the lutefisk worked great – the skunks are gone.
“Now, how do I get rid of the Norwegians?” 
What on God’s green Earth ever prompted the first person to mix lye and fish?
“Hey, Grog, I’ve got some fish. You got any tartar sauce?”
“Nope. Got some lye, though.”
“That’ll do, I guess.”
WTF?
Presumably it was done to preserve said fish, on the principle that even food-spoilage pathogens have some sense of taste 
Isn’t lye poison? What do they do to neutralize that?
They soak it in regular water to remove the lye. Hominy is made using lye, too.
Baccala is the same stuff, minus the lye. Very tasty.
The fish is first dried to preserve it. You can’t make lutefisk out of fresh fish.
Dried fish keeps a very long time. Unfortunately, it’s also about as easy to eat as a wooden plank. You have to add the water back somehow. This is going to involve soaking it, of course, but how the lye first got put in the soak water is a total mystery. As An Arky says, the fish is soaked in plain water - several changes of plain water, actually - to remove the lye, a process that takes days. No lye is left in the finished product, so it won’t kill you, although to my mind that’s about the only nice thing you can say about it.
(Gawd help me, I’m married to a man who loves it.)
Lutefisk is a great dish, no matter what those yahoos say about it.
It’s the only fish you can spread on toast, don’tcha know?
I’m not sure the fact that you can spread it on toast is a recommendation.
Olives can be lye-cured as well, FYI.