01 - Preheat oven to 200°F. Line two baking sheets with parchment paper.
02 - Combine egg whites and cream of tartar in a grease-free mixing bowl. Beat with an electric mixer on medium speed until soft peaks form.
03 - Gradually add granulated sugar, one tablespoon at a time, beating on high speed until stiff, glossy peaks form, about five to seven minutes.
04 - Add salt and vanilla extract. Beat until just combined.
05 - Fit a piping bag with a large star or round tip. Using a food-safe brush, paint one red stripe, one blue stripe, and leave one plain inside the bag for a red, white, and blue effect.
06 - Carefully spoon the meringue mixture into the prepared piping bag, taking care not to disturb the colored stripes.
07 - Pipe 1 to 1.5-inch wide kiss shapes onto the prepared baking sheets, spacing about 1 inch apart.
08 - Bake for 1 hour and 15 minutes until dry and crisp. Turn off the oven and let meringues cool inside with the door closed for 1 hour.
09 - Once cooled, gently peel the meringues off the parchment and store in an airtight container at room temperature for up to five days.