sweet onion
See also: onion
Also known as: Sweet Onions
An onion variety -- Vidalia and Walla Walla are the best-known examples -- bred to be milder and higher in sugar than standard yellow onions, with less of the sharp bite that makes raw onion sting. Its higher water and sugar content make it good eaten raw but also mean it browns and caramelizes faster than a standard onion, so it can scorch if treated the same way.
Buying guidance
Look for onions that feel firm and heavy for their size with dry, papery skin -- sweet onions bruise and spoil faster than standard yellow onions because of their higher water content, so buy them closer to when they'll be used.
Substitutions
- Yellow onion -- sharper and less sweet raw, but a fine substitute once cooked, when the difference in pungency mostly cooks off.
- Red onion -- also mild enough to eat raw, with a sharper bite and a different color; good where color in a salad matters.
- Shallot -- milder and sweeter still, but much smaller, so use more of them by count to match volume.
Tips & common mistakes
Their higher sugar content means they caramelize and can go from browned to burnt faster than a standard onion at the same heat -- use slightly lower heat and check them a bit earlier than you would a standard onion cooked the same way.
Storage
Because they hold more water than standard onions, sweet onions bruise and spoil from the inside more easily and don't keep for months in a pantry basket the way standard yellow onions do -- store them unwrapped and not touching each other in the refrigerator crisper, and use within a couple of weeks rather than treating them as a long-term pantry staple.