In a mixing bowl, use a whisk attachment if you have it and beat egg whites and cream of tartar until stiff peaks form.
Once eggs form stiff peaks, continue beating on medium-high as you add sugar gradually, taking 2 full minutes to add the 3/4 cup of sugar in a constant stream or 1 tablespoon at a time.
Add vanilla, sea salt and continue beating on high until mixture is glossy and almost glue-like in consistency, about 5 more minutes.
Scoop whipped egg white mixture into piping bag with a medium star tip, and pipe into cookie size of choice (1-1/2 inches is what the recipe is based on) about 1/2 inch apart. Cookies will not expand much when baked.
Bake for 40 minutes at 250* or until firm to touch and starting to become golden around the bottom edges. Then turn oven off, leaving door closed and cookies inside, for an additional hour.
Store in an airtight container for up to a week, or in the freezer for up to 6 months.
Recipe by Cara Comini of Health Home and Happiness. Visit us at healthomeandhappiness.com