In a medium bowl, whisk together the flour, 1 tablespoon sugar, baking powder, and salt.
In a separate bowl, combine the water, melted butter, and vanilla extract.
Gradually add the wet ingredients to the dry ingredients, stirring until a dough forms.
Preheat the air fryer to 375°F and lightly spray the air fryer basket with cooking spray.
Using a small cookie scoop or your hands, form the dough into bite-sized balls (about 1 inch in diameter).
Place the dough balls in the air fryer basket in a single layer, making sure they are not touching.
Air fry the churro bites for 8-10 minutes, or until they are golden brown and cooked through.
While the churro bites are cooking, mix the remaining 1/2 cup sugar and cinnamon in a shallow bowl.
Once the churro bites are done, remove them from the air fryer and immediately roll them in the cinnamon-sugar mixture until fully coated.
Serve warm and enjoy!