COMBINE strawberries and 1/3 cup granulated sugar. Let stand for at least 30 minutes to develop juices.
PREHEAT oven to 375° F. Combine baking mix, milk, 3 tablespoons sugar and butter in medium bowl until soft dough forms. Stir in 1 cup morsels. Drop by 8 spoonfuls onto ungreased baking sheet. Press exposed morsels lightly into dough.
BAKE for 15 to 17 minutes or until golden brown. Spoon strawberry mixture over warm shortcakes. Top with whipped topping and remaining morsels.