Whisk together milk, sweetened condensed milk, egg yolks, coffee granules and 1 teaspoon cinnamon in a medium saucepan.

Cook over medium heat, stirring frequently for 15 minutes or until mixture reaches a gentle boil and coats the back of a wooden spoon.

Remove from heat, add rum and vanilla extract.

Serve at room temperature or chilled topped with sweetened whipped cream and sprinkled with cinnamon.