Make the churro dough

• Bring the water, butter, sugar and salt to a boil in a saucepan.
• Remove from the heat, add the flour all at once and stir 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.
• Pipe small churros onto a tray or piece of baking paper and snip them with scissors.

Fry the churros

• Heat the oil to about 175 °C.
• Fry the mini churros in batches until golden and crispy, turning them as needed.
• Drain on paper towels.

Coat in cinnamon sugar

• Roll the warm churros in the cinnamon sugar until evenly coated.
• Serve immediately.