Everyone loves these classic meringue cookies! They're lighter than air, super crunchy, and naturally fat free! I like to make mine small, about 1-1.5 inches, but you can experiment with making larger ones if you'd like--just be sure to adjust the cooking time accordingly.
Preheat the oven to 200 degrees Fahrenheit (90 C). Place the room temperature egg whites in the clean bowl of a stand mixer fitted with a whisk attachment. (Alternately, you can use a large bowl and a hand mixer with the whisk attachments.)
Turn the mixer to medium speed and beat until the egg whites are foamy. Turn the mixer off, add the cream of tartar, and beat again on medium until the whites have turned an opaque white color and just start to hold soft peaks.
At this point, start adding the sugar a few spoonfuls at a time with the mixer running. Adding the sugar slowly helps it incorporate and prevents the meringue from becoming grainy. Continue to add the sugar very gradually, and once all of the sugar is added, add the pinch of salt. Beat the egg whites until they are very thick, glossy, and a shiny white color. When you stop the mixer and lift the whisk out of the whites, the whites should have a very stiff peak. This process will take about 5-10 minutes in a stand mixer.
Finally, stop the mixer, add the vanilla extract, and mix it in briefly. If you want to color the meringues just one color, add a small amount of gel food coloring to the mixing bowl and fold it in to the meringue mixture with a spatula, stirring gently. If you want to make multiple colors, divide the meringue first and work quickly to color each batch your desired color.
Cover two baking sheets with parchment paper. Scoop your meringue mixture into a piping bag fitted with a large tip—a star tip or a round tip both work well. Put a dab of meringue mixture under the corner of each parchment sheet to stick it down and make piping easier.
Pipe stars or kisses of meringues on the baking sheets, about 1 – 1 ½ inches wide. The meringues will barely spread, so they can be piped close together. Bake the cookies at 200 F for 60 minutes. After an hour, turn the oven off, keep the door closed, and allow the meringues to sit until completely cool, for about an additional hour.
Once the meringues are crisp and room temperature, carefully remove them from the parchment paper.
Meringues can be stored in a cool, dry place in an airtight container at room temperature for 3-4 days. If they become chewy, you can revive them by placing them back in a 200-degree oven for about 15 minutes. Let them cool completely, then test them—they should be crispy again!