Whipping The Meringue
Preheat your oven to 150 C/ 350 F
In the cleaned bowl, add the cream of tartar and start whipping your egg whites with the hand mixer on low speed. Do this for 1-2 minutes until it is shy of forming soft peaks.
Gradually add teaspoonfuls of the sugar into your egg whites and increase the speed to medium. Once all the sugar is gone, increase the speed to high and whip it until it's glossy and forms stiff peaks. To tell if it's done or not, rub a bit of the mixture between your fingers. If you can still feel sugar granules, beat again. It should be all smooth. Whip in the salt and flavoring of choice in the end.