Step 1

Heat the oven oven to 215°F. Arrange a rack in the middle of the oven and heat to 215°F. Line a baking sheet with parchment paper and set aside.

Step 2

Begin whisking the egg whites with the whisk attachment on medium low. Place the egg whites in the bowl of a stand mixer fitted with the whisk attachment. (Alternatively, use an electric hand mixer or whisk and large bowl.) Be sure that the mixing bowl and whisk are free from grease and that the egg whites do not have any bits of egg yolks in them. Being whisking or beating on medium-low speed.

Step 3

Add in the cream of tartar, vanilla, and salt, if using. Beat in the cream of tartar, vanilla, and salt, if using.

Step 4

Increase speed to medium and start adding sugar. After the whites begin to foam, bump up the mixer to medium speed and gradually start adding in the sugar. As the eggs whites are whisked, air is incorporated. Little air bubbles will start to form and the egg whites will foam. They will still be too liquidy to hold any shape. Once they begin to foam, begin adding in the sugar, a little bit at a time.

Step 5

Watch for the "soft plop" stage. The foam and air bubbles will start to tighten and the whites will become opaque. The "soft plop" stage describes eggs whites that hold onto the whisk but do not form peaks.

Step 6

Add the remaining sugar as the whites turn into "soft peaks." Continue adding in the sugar until the whites begin to form soft peaks. Here, the whites will begin to hold their shape, but will eventually slump over and melt back into the bowl.

Step 7

Increase the speed to medium-high. After the whites begin to hold their shape, bump up the mixer to medium-high speed until they hold firm peaks.

Step 8

Watch for the "firm peaks" stage. Firm peaks are achieved when whites hold their shape. If you pull the whisk straight out of the bowl, a peak will form. At this stage, the tip of the peak will fold back over onto itself.

Step 9

Add gel food coloring or additional flavors, if using. Mix in a tiny bit of gel food coloring or other extracts until the whites hold stiff peaks.

Step 10

Watch for the "stiff peaks" stage. The stiff peaks stage is what we are trying to achieve. At this point, the peaks should stand up nice and straight. The whites will be glossy and smooth. If you rub a bit between your fingertips, it should feel silky (meaning the sugar has completely dissolved.)

Step 11

Fold in any other ingredients, if using. Gently fold in chopped nuts, chocolate, etc. with a large rubber spatula.

Step 12

Fill the piping bag with meringue. Fit a piping bag with a plain or star tip. Unfold the top of the piping bag about halfway, then use a rubber spatula to fill the bag with the meringue. Fill the bag only 1/2 to 3/4 of the way full to prevent the meringue from spilling out the top of the bag.

Step 13

Pipe out the meringues. Gently squeeze the piping bag to push out any air pockets before getting started. Pipe meringue kisses by holding the bag perpendicular to the baking sheet. Hover the top slightly over the sheet and pipe a "kiss" of meringue: pipe the meringue, stop pressing the bag, then pull up on the bag. (Alternatively, you can use a soup spoon to scoop large, rustic meringues.)

Step 14

Bake for 60 to 90 minutes. Depending on the size of your meringue, bake for 60 to 90 minutes, or until the outside is crisp and the inside is dry yet chewy. They should feel light and hollow. When done, the meringues should easily peel off the parchment paper. Turn the oven off, crack the door open, and let the meringues cool completely in the oven.