Delicious and easy enough for preteens to prepare on their own.
2 egg whites
0 pinch salt
⅔ cup sugar
1 Tbsp lemon juice
Preheat oven to 400. Line 2 baking sheets with parchment paper.
Beat egg whites and salt at high speed in the (small) bowl of a stand mixer till frothy. With mixer still at high speed, gradually add sugar while continuing to beat until sugar is well incorporated (not grainy) and meringue is stiff. On low speed add lemon.
Drop rounded teaspoons of meringue onto the baking sheets, spacing 2" apart. Set baking sheets into oven and immediately turn off the oven. Let cookies remain in oven overnight, before peeling them gently off the parchment.
Store in airtight container.