Beat egg whites, salt and cream of tartar into soft peaks.
Gradually add granulated sugar replacement, vinegar and vanilla.
Beat until mixture forms stiff peaks.
Cover cookie sheet with parchment or plain paper.
Draw eight 4 in. (10 cm) circles; divide meringue evenly among circles.
Using the back of a spoon, shape into nests.
Bake at 250°F (120°C) for 45 to 50 minutes.
Turn off heat an allow to dry in oven for about 1 hour.