In a medium saucepan, combine 1 cup of filtered water, ½ cup of butter, 2 tablespoons of sugar, and ¼ teaspoon of salt. Heat over medium until the mixture comes to a rolling boil. Once boiling, quickly remove it from the heat and stir in 1 cup of all-purpose flour until the dough forms a smooth ball, about 1-2 minutes.

Let the dough cool slightly for about 5 minutes. Add 2 eggs one at a time, mixing until the dough is glossy and smooth.

Transfer the churro dough into a piping bag fitted with a star-shaped nozzle.

In a deep pan, pour in enough neutral oil to submerge the churros, about 2-3 inches deep, and heat to a steady 350°F (175°C).

Carefully pipe lengths of dough into the hot oil, cutting off the ends with scissors.

Fry the churros for 2-3 minutes on each side until golden brown and crispy.

Remove the churros and let them drain on a paper towel. Immediately roll them in a mixture of sugar and cinnamon.

Once cooled slightly, melt ½ cup of chocolate and use a piping bag to fill each churro.