1. In a medium saucepan cook and stir bittersweet chocolate over low heat until melted. Gradually whisk in milk. Meanwhile, in a small bowl stir together sugar, cornstarch, cocoa powder, and salt. Whisk sugar mixture into chocolate mixture.

2. Cook and stir over medium heat until thickened and bubbly. Cook and stir for 2 minutes more. Stir in vanilla. Remove from heat; cool for 45 minutes. Whisk mixture until smooth.

3. Spoon mixture into nine 3-ounce frozen pop molds.* Add sticks; cover and freeze for 3 to 4 hours or until firm. Let stand for 10 minutes before unmolding. If desired, dip pops in melted white chocolate and chocolate pieces, and/or dip in melted dark chocolate and shortbread cookies.

*Tip:

If frozen pop molds are unavailable, use 3-ounce wax-lined paper cups instead. Spoon chocolate mixture into cups; cover each top with a piece of foil. Using a small sharp knife, make a slit in each piece of foil. Insert wooden pop sticks into slits. Freeze and serve as directed.