Place the egg whites in a mixer bowl. Start mixing on low and gradually increase to high speed. Add the sugar gradually until white peaks form.
Turn the mixer to low speed. Add 1 Tablespoon lemon juice or apple cider vinegar, plus 1 Tablespoon of corn starch or potato flour. Mix on low for 10-15 seconds until all ingredients are combined.
Transfer mixture to the center of a cookie sheet lined with parchment paper. Using a spatula, form an 8-inch circle, where the center is lower than the edges and the outer walls are a bit higher, like a shallow bowl.
Place it in a 325° degrees preheated oven and lower the heat to 225° as soon as you place the meringue in the oven. Bake for 90 minutes. Turn off the oven and leave the meringue in there until cooled. This can be done a day ahead of time.
Whip the heavy whipping cream plus 1 teaspoon of sugar until firm. Scoop and spread in the middle of the baked meringue.
Top with any mix of berries or any sliced fruit you like. (1 to 2 cups in total).
