Heat oven to 300°F. Line two baking sheets with parchment paper or coat lightly with oil.
In a large bowl, beat egg whites and salt to firm peaks. Add condensed milk and vanilla and fold gently with a rubber spatula until mostly combined. Fold in the coconut until combined.
Place generously-rounded-tablespoon sized mounds onto baking sheets 1 inch apart. Bake until bottoms and/or peaks brown, 20 to 25 minutes. Let cool on racks. Best eaten fresh. Store in airtight container up to a week, or freeze.