1. Preheat the oven to 200 degrees F.
2. On parchment paper, draw an 8-inch circle or (2) 4-inch circles.
3. Using an electric mixer, beat egg whites, cornstarch, and cream of tartar in a glass bowl until frothy.
4. Gradually beat in ½ cup sugar slowly, 1 Tbsp at a time until soft peaks form.
5. Spread merengue on parchment lined baking sheet with your parchment paper circle on top.
6. Fill in the circle with merengue, ¾-inch thick in the center and more around the edges 1½ -inch thick so you’ve created a well in the center.
7. Bake merengue in oven until firm to touch (about 3 hours).
8. Turn off oven and let it cool for about 2 hours.
9. About 30 minutes before serving, toss strawberries, lemon zest, and 1 Tbsp sugar in a bowl  to get the fruit juices running.
10. Carefully transfer the merengue to a serving platter and fill the well with yogurt.  Top with berries and basil.

**Merengue can be made a day or two ahead of time. Store airtight in a cool, dry place.**