- Preheat the oven to 225°F. Line two baking sheets with parchment.
- In the bowl of stand mixer, combine the egg whites, cream of tartar and salt. Beat until soft peaks form.
- With the mixer running at medium speed, gradually add the maple sugar. Beat until the mixture is stiff and glossy.
- Scoop by the quarter cup for large meringues, or pipe in walnut-sized mounds for small meringues. Sprinkle each meringue with a light dusting of additional maple sugar.
- Bake the meringues for 1 hour. Turn off the heat, and leave the meringues in the oven, with the door closed, until they're crunchy all the way through — at least 3 hours or preferably overnight.
- Once the meringues are dry, remove from the oven, and store airtight at room temperature.