HEAT oven to 400°F.
MIX first 4 ingredients in large bowl. Stir in 1/2 cup granulated sugar. Cut in butter with pastry blender or 2 knives until mixture resembles coarse crumbs. Add next 3 ingredients; mix well. Pour into 2 greased and floured 9-inch round pans. Mix remaining granulated sugar and the brown sugar; sprinkle over batter.
BAKE 12 min. or until toothpick inserted in centres comes out clean. Cool cakes in pans 10 min. Remove from pans to wire racks; cool completely.
MELT semi-sweet chocolate as directed on package. Place 1 cake layer on plate; top with half each of Cool Whip and berries. Cover with second cake layer. Top with remaining Cool Whip and berries; drizzle with semi-sweet chocolate.
serving size = 1 piece (92 g)