Making pot stickers.........recipe calls for the green of 2 scallions. Can I use sweet onion instead and how much.
You can substitute but you will not get the color. It is looking for. Remember the onion will be stronger in flavor than green part of a scallion do I would use less. A shallot might be a better substitution if you have one.
Besides the color, the flavor will be different - scallions are fairly mild, and not sweet. A sweet onion (assume you mean vidalia or walla walla or such) have a stronger and, well...sweet taste. Maybe you'll invent something good, but the flavor will be different than a traditional Chinese pot sticker. If you make that sub, I'd go light on the onion, to avoid a pronounced sweet taste.
I agree with these two comments. Onions have a distinctly different flavor from scallions and don't have the green color you're looking for. I would finely mince the onions or scallions so as not to get a big bite of onion. Also, they will be juicy, so I would dry them in a paper towel. Another good substitute would be fresh chives. Good luck!
Yes chive would be an excellent substitution
jmburns: I use a LOT of chives. I'm lucky to have them growing proliferatively in my garden. I love the flavor of them in anything, especially chopped into a salad. I hope amysarah decides to try some and let us know how she liked them.
Actually, I also have a pot of chives (that's miraculously lived for years) and use them very often. (One of my favorites, in fact.) My understanding of the original question was that she had sweet onions on hand, but not scallions - i.e., she was just asking about that specific sub. But who knows, maybe she has some chives around too...in which case - sure, use 'em.
Why not use what you have on hand? Sure the result might not be PRECISELY the same, but a recipe is not a formula. And why waste time and/or gas running to the grocery store every time there's a call for an ingredient that might lend itself to a little substitution? I can't count how many times I've substituted a bit of onion for called-for shallots. and I've done the same with scallions when I had none.