How do I tone down the intensity of raw onion?

Question

How can I tone down the intensity of raw onion?
Some onions have a more acute taste and smell than others of the same type, and I would like to avoid them in salad dish, or making dips with raw onion. If effectively none, an alternative solution that can also be helpful is to find out what condiments can I add/mix with raw onion to cancel out the intensity of the the acute taste.

[EDIT]
There is a uniquely (IMHO) sweet taste to onion that I like. But accompany with that is the acute scene and flavor to it that I wanted to get ride of. I do not want to waste away the taste of onion, but remove the acuteness and remain the sweetness.

Answer

Two things control the "sharpness" of onions: variety and age. While certain varieties of onions are sharper than others (i.e. Reds, walla-walls and vidalias are sweeter), any onion which has been in storage too long is going to be sulphurous and sharp-tasting. Since it's January now, that's going to be pretty much all onions.

Since onion sharpness comes from sulphur compounds (as I understand it), the best way to sweeten onions is to release some of them ahead of using the onion. The best way to do that is:

1. Slice the onion thinly, crossways (parallel to its equator rather than pole-to-pole).

2. Place the sliced onion in a wide bowl, uncovered or very loosely covered, in the fridge or other cold place for at least an hour and up to a day.

Additionally, either vinegar or salt -- or both -- will help accelerate removing sharpness from onion. For example, for a New Year's Eve appetizer this year I sliced a red onion in to rings, tossed it with 1/2 tsp salt and 2 tsp red wine vinegar, and left it in an open bowl on the 45F porch for 5 hours. The result was intensely sweet red onion which could then be used as a canape topping.

If you're in a hurry, though, the only way to make the onion less sharp is to cook it.

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