Parve knife

My babysitter didn’t realize and used a parve knife to cut hot lasagna. It has been more than 24 hours since the knife was used to cut onion. Is there a way to Kasher the knife so that we can continue using it for parve foods?

Thanks a lot!

Yes.
Hagalah

Meaning boil a pot of water (any type) that is large enough to cover the entire knife.
Wait till the pot is bubbling, uncover the lid, put the knife in.
Then spill in the sink and rinse the knife w cold water.

That’s it. You’re done.

Thank you so much! Chodesh Tov!

Thank you

What if the knife has a wooden or plastic handle? May one still kasher it in this manner? Thanks.

Yes

Can one use hagalah on a dairy knife and then use the knife for meat, or vice versa.