In a medium saucepan, combine 1 cup of water, ½ cup of unsalted butter, ¼ teaspoon of salt, and ½ cup of sugar. Bring the mixture to a boil over medium heat, stirring occasionally.

Once boiling, remove from heat and quickly stir in 1 cup of plain flour until a smooth dough forms, resembling a thick paste.

Allow the dough to cool for 4-5 minutes in the pan. Once slightly cooled, add 1 beaten egg and 1 teaspoon of vanilla essence. Mix until smooth and glossy.

Preheat your air fryer to 375°F (190°C) and lightly spray the air fryer basket with nonstick cooking spray.

Transfer the dough into a piping bag fitted with a large star tip. Pipe out bite-sized churros into the basket, leaving space between them.

Lightly brush the churros with melted butter and air fry for 10-12 minutes, checking that they turn golden brown.

In a separate bowl, mix ½ cup of white sugar with 2 teaspoons of cinnamon powder. Toss the warm churros in this mixture immediately.