In a medium sauce pot bring water, butter, salt and sugar to a low boil. Add in flour and stir until mixture comes together and begins to roll into a ball and becomes shiny. Turn off heat and continue to cook, stirring for an additional 2 minutes. Remove from heat and allow to cool.
Once cooled but still warm stir in eggs and vanilla one at a time until incorporated.
Place dough into a pastry bag fitted with a medium star tip
Heat 2-3 inches of canola oil to 375 degrees in large heavy bottom pot or a shallow saute pan with high sides. Carefully squeeze 3 inches of pastry dough into the hot oil, cutting off each churros by swiping off at the tip with your finger or a knife. Oil will bubble around the churros vigorously- when bubbles begin to die down and churros are golden- flip over and repeat, about 1 minute on each side.
Place cooked churros onto paper towel to drain off excess oil and toss in sugar and cinnamon.
Sauce:In a small sauce pot warm cream with cinnamon stick and zest- for about 5-10 minutes.
Place chocolate into a bowl and pour strained cream over the chocolate- allow to sit for 5 minutes. Whisk smooth and serve warm