If you’ve never sprinkled a little finishing salt on a steak, chop, or slice of fresh tomato right before you serve it, try it, you won’t be disappointed. Just a little will do — you don’t want to oversalt your dish, but if that dish is hot or moist, it’s not uncommon for the salt to just dissolve as soon as you sprinkle it on — that’s why it’s done table-side in many restaurants. At home, you can beat the clock by spraying a little cooking spray into a small bowl, adding just enough salt or salt flakes as you want to use for everyone’s plates, and stirring it around with your fingers a bit. The oil in the bowl coats the flakes and when you sprinkle it over your food, it’ll dissolve a bit more slowly, giving you time to enjoy the taste and the crunch.
How to Preserve A Finishing Salt’s Crunch [America’s Test Kitchen]