Preheat oven to 250F, with the rack in the center of the oven.

3 large egg whites
1/4 teaspoon cream of tartar
3/4 cup superfine sugar
1/4 teaspoon pure vanilla extract

Line a baking sheet with parchment paper. You can form the cookies with a pastry bag fitted with a 1/2 inch (1.25 cm) plain tip, or I often just use two spoons to make the cookies.

Beat the egg whites on low-medium speed until foamy.

Add the cream of tartar and continue to beat the whites until they hold soft peaks.

Add the sugar, a little at a time, and continue to beat, on medium-high speed, until the meringue holds very stiff peaks. Beat in the vanilla extract. The meringue is done when it holds stiff peaks and when you rub a little between your thumb and index finger it does not feel gritty.

Use a piping bag or simply spoons to place meringues on the parchment paper.

Bake for approximately 2 hours, rotating the baking sheet half way through. The meringues are done when they are pale in color and fairly crisp. \

Turn off the oven, open the door a crack, and leave the meringues in the oven to finish drying several hours or overnight.

The meringues can be covered and stored at room temperature for several days.

Cribbed from http://www.joyofbaking.com/MeringueCookies.html