In a saucepan, combine the water, unsalted butter, salt, and sugar. Bring the mixture to a boil over high heat, then reduce the heat to low. Gradually add the flour, stirring constantly until a smooth, cohesive dough forms and pulls away from the sides of the pan. Remove from heat and set aside.

Transfer the dough to a large mixing bowl and allow it to cool slightly for 4–5 minutes. Once the dough is warm—not hot—add the egg and vanilla extract. Using an electric hand mixer or sturdy wooden spoon, mix thoroughly until the dough becomes smooth and glossy, with no lumps remaining.

Spoon the churro dough into a piping bag fitted with a star tip. Preheat your air fryer to 375°F (190°C) and lightly coat the basket with nonstick spray, such as coconut or avocado oil. Pipe small bite-sized churro shapes directly into the basket, leaving space between each to prevent sticking. Alternatively, spoon the dough into small mounds for a more rustic look.

Lightly brush the tops of the churros with melted butter to enhance browning. Air fry for 10–12 minutes, or until golden and crisp. Depending on your air fryer’s size, you may need to cook them in batches to avoid overcrowding and ensure even cooking.

While the churros are frying, mix the sugar and cinnamon together in a shallow bowl. Once the churros are done, transfer them immediately into the cinnamon sugar mixture and gently toss to coat. For extra adhesion, lightly brush the churros with melted butter or spray with water/nonstick spray before tossing in the sugar.

Serve warm with your favorite dips like chocolate sauce, caramel, honey, or Nutella. These sweet and crispy churro bites make the perfect treat for parties, movie nights, or whenever you’re craving something indulgent and comforting.