Cut brownies into 1 1/2-inch pieces. In 4-quart trifle bowl or glass serving bowl, layer half of the brownie pieces and 1 1/2 cups of the cherries with liquid. Spoon chocolate whipped topping mixture over cherries. Repeat with remaining brownie pieces, cherries with liquid and plain whipped topping. Cover; refrigerate until serving. Shave 1 oz bittersweet chocolate. Sprinkle over trifle. Store covered in refrigerator.