Churros rellenos

Instructions

1. Bring the water, butter, sugar and salt to a boil in a saucepan.
2. Off the heat, add the flour all at once and mix vigorously until you get a smooth ball that pulls away from the sides.
3. Let it cool for 5 minutes, then beat in the eggs one at a time, working the dough until glossy.
4. Spoon the dough into a piping bag fitted with a star nozzle and set aside.
5. Heat the oil to 180 °C and pipe 10 cm sticks directly into the oil using a damp knife to cut them off.
6. Fry for 3 to 4 minutes, turning, until well golden, then drain on paper towels.
7. Mix the sugar and cinnamon, and roll the churros in it while still warm.
8. Pierce one end of each churro and fill them with dulce de leche using a fine piping bag, then serve right away.