Preheat oven to 200 degrees. Set oven racks so you can get in 2 cookie sheets at once.

Start whipping egg whites. Add salt and vanilla. Slowly add sugars, whipping all the while. Continue whipping mixture until stiff-ish.

Place mixture into quart-sized sandwich bag. Snip off corner of bag and pipe mixture onto cookie sheet lined with parchment paper or Silpat. Make cookies no larger than a quarter, otherwise you get gooey centers.

Bake at 200 degrees for 2 hours.