When a recipe calls for a small onion, I figure about 1/3 cup, for medium, 3/4 cup and for large, 1 1/4 cups. There's no scientific evidence for that, just my best guess. If the recipe just says "one onion, chopped", I use 3/4 cup.

I don't think the size of the dice would affect the flavor as much as the texture and appearance in the dish.

The smaller the onion is chopped/minced the more essential oil is released. So, grating an onion will be considerably more powerful than, say, quartering the onion and tossing it into a pot of soup.

Members of the Allium genus (which includes garlic, onion, leek) are booby trapped. Around the cells there is a liquid that when combined with a chemical from the cell's interior creates a series of sulfur compounds. The more the cells are damaged and exposed to oxygen by cutting or crushing, the more of these sulfur compounds are generated.

/tricia

Welcome Melvie, I think you are safe using Ruthanna's suggested measurements.

I don't tend to worry about size of onion though. It just depends on what I am making. For things like soups and stews it really isn't going to matter much if you add more onion than a recipe calls for. It is probably only important if you are making something that is more "delicate" . Just a matter of personal preference.

Again, welcome and hope you will continue to post.

Ann

I agree that Ruthanna's measurements are safe to use, and if the amount of onion were critical, the recipe should give the amount in cups. The onions I get yield more than that, but I think I must be buying ones that are especially large.

Tricia is right that chopping the onion smaller will release more flavor; this is why recipes will specify a rough chop, coarse or fine chop, or mince. You get more health benefits from a fine chop or mince, although it will cook more quickly.

Lars

Welcome Melvie! Glad to see you are out in the open!

I make a lot of soup and I don't really measure onions. I do agree with triciae that the smaller dice produces a more pungent smell therefore more flavor.

I think you are safe with a guestimate (or Ruthanna's suggestion) on the sweet onions that are in season now - Texas Sweet or Vidalia onions. In the winter when I buy yellow onions the flavor can vary greatly. Some are very strong. Therefore I rely on smell at times when I have a particularly strong onion.

Welcome out of lurkdom!
Teresa

I never measure onions either, but as Teresa says, I go by the onions. The ones I have right now are small but pungent, so I still use one. If they were larger and sweeter, I'd still use one that was not as strong.

I agree with Ruthanna's measurements, you'll do fine. Most recipes calling for onions don't rely on them as a critical major component, so exact measurement is unnecessary. I do tend to cut mine smaller because I don't like to get a big chunk of slightly crunchy onion in foods that are otherwise cooked through.

I use a lot of onions, it seems like I put them in nearly everything.

Welcome to the forum.

Annie

Thank you all for your advice and kind words! Looks like its been a little over a week since I checked in which is about right for me. Like I said I love this forum and feel like I know some of you personally from all the posts I've read over the years!

For something like soup... whatever you like!?! I like onions, so might go heavy on them. Think exact amount come into play when baking... a "science" thing?