Yes, you can freeze onions! You don’t even need to blanch them or pre-treat them in any way. It’s super easy! Simply peel, chop (diced or sliced) and freeze.
How do you store onions long term?
Can you save half of an onion?
THE BOTTOM LINE: Store leftover halved onions wrapped tightly in plastic wrap or in a zipper-lock bag or airtight container in the fridge for up to two weeks. Be sure to use the stored onions only in cooked applications. Stored properly, a leftover halved onion works fine if cooked but not raw.
Should you refrigerate onions?
Refrigeration is only necessary when trying to extend the shelf life of sweet or mild onion varieties with high water content, but be sure to use a low humidity setting; they must be kept dry. Refrigerate whole peeled onions after purchasing. Store cut onions in a sealed container for up to 7 days.
David Nilsen is the former editor of Fourth & Sycamore. He is a member of the National Book Critics Circle. You can find more of his writing on his website at davidnilsenwriter.com and follow him on Twitter as @NilsenDavid.