In a medium size pot, combine 2 cups of whole milk, egg yolk, guava paste (chopped), vanilla extract, sugar, and cinnamon sticks. Bring to a boil over medium heat. Whisk frequently to help dissolve the guava and prevent the milk from sticking. About 5-10 minutes.
In a measuring cup, add the remaining 1/3 of whole milk and sift the corn starch into it one tablespoon at a time, stirring in between tablespoons.
Once the milk begins to boil and the guava is dissolved. Stir the milk and cornstarch mix one last time and then strain it into the hot milk. Mix to combine. Allow the mixture to boil for 1-2 more mintues. You will notice the mixture will become thick.
Once combined and the pudding is thicker, strain the pudding into a storage container. Place in the fridge to cool. When ready to serve, sprinkle with Maria cracker crumbs and enjoy!!