Preheat oven to 250ºF. Line two baking sheets with parchment paper.

Place the reserved egg whites in a large bowl. Add ¼ teaspoon cream of tartar and ⅛ teaspoon salt. Beat with an electric mixer on medium speed until foamy, about 3 minutes.

Begin adding the sugar 1 tablespoon at a time, beating at high speed after each addition until the sugar dissolves. Continue beating the egg whites until they become thick and glossy. Once the eggs reach stiff peaks, turn off the mixer. This requires 10 to 12 minutes of consistent mixing.

Attach a star tip to a pastry bag. Transfer the meringue mixture to the bag. Pipe the meringues into 1-inch-diameter circles directly onto the parchment paper, about 1 inch apart. Since the cookies won’t spread in the oven, they don’t need much space between them.

Transfer the sheet pans to the preheated oven for 1 hour. Turn off the oven and open the door slightly. Allow the meringues to cool down gradually for 1 hour.

Remove the meringues from the oven and let them stand for 30 minutes. Then, gently remove them from the baking sheet and transfer them to a serving plate. Enjoy!