For the churros:

1) Heat vegetable oil in a large pot or deep skillet over medium-high heat to 360°F.
2) In a pot heat the water, salt, vanilla extract, and butter over medium heat.
3) As soon as it starts to boil add all of the flour at once and start beating with a wooden stick. When everything is mixed, remove from heat and wait 1 minute.
4) Still in the same pot add the egg and do not stop stirring until a smooth but consistent mixture is formed. Transfer to a 16-inch piping bag fitted with a rounded star tip (no larger than 1/2-inch).
5) Carefully pour mixture into preheated oil, in about 6-inch lengths, cutting off end with clean scissors. Let them fry about 3 minutes per side until golden brown.
6) Transfer them to paper towels to dry briefly, about 15 seconds (don’t wait too long or they’ll dry out and the sugar won’t stick as well). Then pass them into the cinnamon and sugar mixture. Enjoy them with the chocolate ganache still warm.

For the ganache:

1) Heat the crema mexicana over medium heat without boiling.
2) When it is hot and liquid enough, take it off the heat, transfer it to a bowl and add the chocolate chips, and mix until they are completely incorporated.
3) Store at room temperature until consumed, then store in the refrigerator.