- Have all ingredients at room temperature, 68-70 degrees. Preheat oven to 225 degrees.
- Line cookie sheets with plain parchment paper. Trace two 8- or 9-inch or three 7-inch circles on the parchment, leaving an inch between them, and turn parchment upside down so the tracing shows through but cannot transfer to the meringue.
- In a large bowl, beat egg whites, vanilla and cream of tartar on medium speed until soft peaks form. Very gradually add sugar, 1 tablespoon at a time, beating on high speed. Beat until the meringue holds very stiff peaks and has a glossy sheen.
- Shape meringue mixture into bowl-shaped mounds by placing dollops within the circles on the parchment and using the back of a spoon to make a well in the center.
- Bake for approximately 1 ½ to 2 hours. Meringues should have a hollow sound when tapped and feel firm to the touch. Turn off heat and leave meringues in the oven to cool for 2 to 2 ½ hours.
- To assemble, rinse berries and pat dry. Whip heavy cream with powdered sugar until soft peaks form. Place meringue on dessert plate. Top with berries and whipped cream.