Grease a 9-in. heart-shaped baking pan.

Line with waxed paper; grease and flour the paper.

Set aside.

Prepare cake batter according to package directions; stir in chocolate chunks.

Pour into prepared pan.

Bake at 350° for 25-30 minutes or until a toothpick inserted near the center comes out clean.

Cool for 5 minutes before inverting onto a serving platter.

Spread warm cake with hot fudge topping.

Arrange raspberries over the top.