Asgardian to Jötnar

[sanfuturo]

Does anyone know of a story that has a part wherein it is discovered that it is possible to change Asgardians into Jötnar, and Loki makes sure this is done to Sif, to shut her up and give her a taste of her own bigotry and hatred?

I think it was on AO3, and there were more people than just her who were changed into Frost Giants for their own survival.

There was some historical information that Jotunheim may have been colonized by Asgard, but then the people had to metamorph into something that could survive there.

Thanks for any help you can give!