Preheat oven to 200°F (95°C). Line two baking sheets with parchment paper. Ensure mixer bowl and beaters are perfectly clean and grease-free.

In the clean bowl of a stand mixer with whisk attachment, combine egg whites and cream of tartar. Whip on medium speed until soft peaks form.

With mixer on medium-high, add sugar one tablespoon at a time, letting it incorporate fully. Once added, whip on high for 5-7 mins until stiff, glossy peaks form.

Reduce speed to low, add peppermint extract (and food coloring if using). Mix just to combine. For color, fold gently once or twice with a spatula for a swirl effect.

Gently fold in about 1/3 of the crushed candy canes with a spatula, being careful not to deflate the meringue.

Pipe or spoon meringue into 1.5-2 inch kisses or rosettes onto prepared sheets. Sprinkle tops with reserved crushed candy.

Bake for 1 hour 30 minutes. Do not open door. Turn oven off and let meringues cool completely inside the oven (2+ hours or overnight).

Once cool, gently peel meringues from parchment. Store in an airtight container at room temperature.