Prepare the dough base: In a saucepan, combine 1 cup water, ⅓ cup + 1 Tbsp unsalted butter, 1 tsp salt, and 2 Tbsp sugar. Bring the mixture to a boil over high heat. Once boiling, reduce the heat and gradually stir in 1 cup plain flour, mixing continuously until the dough comes together smoothly. Then remove from the heat.

Cool and mix dough: Transfer the hot dough into a large mixing bowl and let it cool for about 4‑5 minutes. Once it’s slightly cooled (so the egg won’t cook on contact), add in the 1 large egg and 1 tsp vanilla essence. Use an electric hand mixer to thoroughly combine the ingredients until you have a smooth mixture.

Pipe the churros: Preheat your air fryer to around 375 °F (190 °C). Spray or brush the air fryer basket with a nonstick cooking spray (a light oil spray works well). Transfer the churro dough into a piping bag (with a star tip if you like the traditional ridged look) and pipe bite‑sized pieces into the basket, making sure not to overcrowd. Alternatively, you can drop spoonfuls of dough.

Cook the churro bites: Lightly brush some melted butter on top of the piped dough (this helps the coating stick). Cook in the air fryer for about 10‑12 minutes until the bites are golden brown and crisp. Depending on your air fryer’s size you may need to cook in batches to avoid overcrowding and ensure even cooking.

Coat with cinnamon sugar: While the bites are cooking, in a shallow bowl combine 1 cup white sugar with 1 Tbsp ground cinnamon. Once the churro bites are done, transfer them directly into the cinnamon‑sugar mixture and toss gently to coat them evenly. If needed, brush or spray them lightly with butter/neutral oil to help the coating adhere.

Serve and enjoy: Serve your churro bites warm, ideally with a dipping sauce such as warm chocolate sauce, caramel sauce, or even honey.