In a medium bowl, mix together the maizena or corn starch with 1 cup of the milk until the corn starch is dissolved and there are no lumps.

Pour the rest of the milk, the sugar, cinnamon stick and the vanilla seeds into a medium pot, then gradually whisk in the corn starch mixture.

Bring the mixture to a boil over medium-high heat, whisking constantly, until the colada is thickened to the consistency of a thin pudding.

Remove from heat, discard the cinnamon stick and serve hot.