Whisk together milk, coffee granules, cornstarch, 1/4 cup sugar, and a small pinch of salt in a heavy medium saucepan. Bring to a boil over medium heat, stirring occasionally, then boil 1 minute, stirring constantly.
Transfer to a metal bowl set in an ice bath and cool, stirring often, about 10 minutes.
Pour into cups or ramekins and chill, uncovered, 20 minutes.
Beat cream with vanilla and remaining 2 tablespoon sugar using an electric mixer just until soft peaks form. Spoon whipped cream onto puddings and dust cream lightly with cinnamon.
