Position a rack in the lower third of the oven and
In a bowl, using an electric mixer on medium speed, beat the egg whites until well mixed. Sprinkle the cornstarch over the whites and continue to beat until the whites are white and foamy. Raise the speed to high and very gradually add the sugar, beating until stiff, shiny peaks form. Quickly beat in the lemon juice and vanilla. Spread the meringue inside the circle drawn on the parchment, building up the edges slightly to form a rim.
Using the electric mixer, chilled clean beaters, and a chilled bowl, whip the cream until stiff peaks form. Spread the curd in the hollow of the meringue. Top with half of the whipped cream and sprinkle with the berries. Let stand for 10 minutes to soften the center of the meringue slightly. Cut into wedges and serve, passing the remaining whipped cream at the table.