Make the churro dough

• Heat the water with the butter, sugar and salt in a saucepan until the butter melts and it comes to a boil.
• Take off the heat, add the flour all at once and stir vigorously until a smooth dough forms.
• Let the dough cool slightly, then beat in the egg until fully incorporated.

Fill the piping bag

• Transfer the dough to a piping bag fitted with a star nozzle.

Fry the churros

• Heat the oil to 180 °C.
• Pipe lengths of dough directly into the hot oil, cutting them with scissors.
• Fry until deep golden on all sides, turning as needed.
• Drain on paper towels.

Coat in cinnamon sugar

• Mix the sugar with the cinnamon.
• Roll the warm churros in the cinnamon sugar until evenly coated.

Make the chocolate sauce

• Heat the cream in a saucepan until it just simmers.
• Pour it over the chopped chocolate and stir until smooth and glossy.

Serve

• Serve the churros warm with the chocolate sauce for dipping.