Preheat the oven to 200°F. Line a sheet pan with parchment paper. Using a 9-inch plate as a guide, draw a circle on the paper. Flip it over so the pencil side is down.
Whip the meringue: In a stand mixer fitted with the whisk attachment (or use a handheld mixer), beat the egg whites and salt on high speed for 1–2 minutes until firm. Gradually add the sugar and continue beating until glossy stiff peaks form (about 2 more minutes).
Add starch and flavor: Sift the cornstarch over the mixture, then gently fold in the vinegar and vanilla with a spatula.
Shape and bake: Spoon the meringue into the center of your circle and smooth it into a rough disk. Bake for 1 hour and 45 minutes. Then, turn off the oven and let the meringue cool inside—with the door closed—for about 1 hour. It should be crisp outside and soft inside.
Make the whipped cream: While the meringue cools, whip the cream until thickened. Add the sugar and almond extract and continue whipping just until soft peaks form—don’t over-whip.
Assemble: Carefully remove the meringue and place it on a serving plate. Gently spread the whipped cream on top, then pile the berries over the cream. Toss the berries with a little sugar if desired.
Serve immediately and enjoy the contrast of textures and flavors!