Combine sugar, cornstarch, and cocoa in a medium saucepan; stir with a whisk. Whisk in milk and cream. Bring to a boil over medium-high heat. Cook 1 minute or until thick and bubbly. Remove from heat. Add chocolate and peanut butter, stirring until smooth. Spoon about 1/3 cup pudding into each of 6 bowls. Top each serving with 1/2 teaspoon peanuts.