HEAT oven to 225°F.
BEAT egg whites and cream of tartar in medium bowl with mixer on high speed until soft peaks form. Add granulated sugar, 1 Tbsp. at a time, beating constantly until stiff peaks form. Spread into 10-inch circle on parchment-covered baking sheet, indenting centre slightly.
BAKE 1-1/2 hours. Cool. Meanwhile, beat pudding mix and milk in medium bowl with whisk 2 min. Stir in Cool Whip. Refrigerate 15 min. or until slightly thickened.
PLACE meringue on serving plate just before serving; fill centre with pudding mixture. Top with berries and icing sugar.