Put both in a small-diameter pan so that the bottom of the pan is well covered and mix 'em up. Cook 'em for a while until they're brown-ish. 20-30mins usually. They will need to be stirred so they don't burn.
Chop the cooked onions up nice and tiny and wait for them to cool before adding the other things.
You can start eating them after a few hours
If you add sugar to help the onions caramelize then the end result will be a sweeter dip which is not really what I want but you might like it.
The salt content will depend on the types of soy and mayo you have. You can always go only-sour-cream (which is generally lower in salt) and adjust the soy sauce to hit your salt budget.
The end result will also be quite different based on the types of sour cream and mayo you choose. Low-fat sour cream + miracle whip will give you a different result from 14% sour cream + homemade mayo. Best to stick to the brands and types you eat normally.
Last updated 2020-10-14