Start by bringing the water, sugar, salt, and butter to a boil in a medium saucepan.
Once it starts bubbling, reduce the heat to low and stir in the flour all at once.
Use a wooden spoon to mix it until a dough forms
Let the dough cool for about 5–10 minutes
Once it’s slightly cooled, beat in the egg and vanilla.
Pour a few inches of oil into a deep skillet or heavy-bottomed pot.
Spoon the dough into a piping bag fitted with a large star tip. Carefully pipe 4–6 inch lengths of dough directly into the hot oil, cutting the end with scissors.
Fry the churros for about 2–3 minutes per side
While the churros are still warm, roll them in a mixture of cinnamon and sugar.
