Preheat oven to 200°F.

Line 2 baking sheets with parchment paper.

In a large bowl, beat egg whites, vanilla, and cream of tartar with a mixer at medium speed until foamy. Increase mixer speed to high, and beat in sugar, 1 tablespoon at a time, until glossy and stiff peaks form.

Option 1 - Drop meringue into eight mounds on prepared baking sheets. Using the back of a spoon, shape meringue into nests, roughly 1 inch high and 4 inches wide.

Option 2 - Transfer the meringue to a pastry bag fitted with a large round tip.  Pipe eight 3-inch disks on the baking sheets, then pipe around the edge of the disks to create 2-inch-high sides.

Place in the lower part of the oven and bake for 2-3 hours, or until the meringues are dry, their centers aren’t sticky, and they are easily lifted from the parchment paper with their bases intact.

Turn off the oven and, without removing, let meringues cool completely for at least one hour, or overnight.

Meringues will keep for several days in an airtight container at room temperature.

Fill shells with assorted berries. Garnish with mint, if desired.

Optional: Fill meringues with a scoop ice cream and dribble chocolate sauce on top

Serve immediately.