Preheat your oven to 225 degrees F. Place silpats or parchment onto 2 cookie sheet pans.
Place egg whites into clean bowl or stand electric mixer. Using the whisk attachment, start whipping on a low speed and as it begins to form continue to increase to medium speed. Sprinkle in salt and continue to whip egg whites. Drizzle in vanilla extract. When you start to see soft peaks forming, add a small amount of the sugar free sweetener. Continue to add small amounts while whipping at a high speed. Continue to whip until the egg whites have started to pull away from the sides of the bowl and you see stiff peaks. If you're unsure if they are stiff, you should be able to flip the bowl over and nothing moves or slips.
Place half of the whipped whites into the decorating tool or pastry piping bag with a star tip.
Make small swirls onto the baking sheet pan using the small circle shape on the silpat or on parchment paper measuring 1.25 inches. Continue with the remaining whipped whites. You should be able to make 44 cookies.
Bake for 2 hours. Then shut the oven off and leave them in the oven for another hour. Remove from the oven and allow to sit out on the counter to completely dry out. This can take a few more hours. Store in an airtight container. We found ours crisp in the center of the meringue the next day.