Ruined my homemade cole slaw salad with 2 chopped yellow onions...very acidic and bad after taste. Recipe calls for the onions. How do I not ruin the salad the next time with the onions?
You don't say how much cole slaw you made with 2 entire chopped onions. I hope it was a lot. (I'm not sure I'm familiar with raw chopped onions at all in cole slaw.)
Did this recipe specify yellow onions? or were they perhaps supposed to be one of the "sweet" onion varieties -- Walla Walla, or Vidalia, etc. Those have a lot less bite, and are better to eat raw than the more sulfurous biting types. Maybe next time you might try using them.
Also, if you aren't wedded to this specific recipe, the obvious solution would be include less chopped onion... or even none, if you aren't happy with its contribution to the result.
I've always found the taste of raw yellow onions to be a little overpowering. Their strong flavour works well cooked in soups, stews and casseroles though. Sweet white or even red onions (in a purple cabbage slaw) works much better to compliment a slaw's flavour.
One place I once lived at in Canada (many miles from a decent grocery store), I was unable to buy sweet onions. In that case, I'd cut a large yellow onion and just take out some of the centre part to use. Since it's the youngest part of an onion bulb (corm actually), it's also the mildest juiciest part. Cutting it and soaking it in a lightly salted water will help draw out some of the stronger taste too. I'd use less onion than I would a sweet onion and still achieve the taste I wanted.
The rest of the yellow onion wasn't wasted and would usually be used the same day (or next) in some cooked mixture. All that was years back when I could eat onions with impunity. Now I stick to shallots or scallions. Really miss having creamed baby onions. :(