Preheat your waffle maker according to the manufacturer's instructions.
In a mixing bowl, whisk together the flour, baking powder, salt, 1/4 cup sugar, and 1 teaspoon of cinnamon until well combined.
In another bowl, mix the milk, vegetable oil, egg, and vanilla extract until smooth.
Slowly pour the wet ingredients into the dry ingredients, stirring gently until just combined. Do not overmix; a few lumps are okay.
Lightly grease your waffle maker with cooking spray or oil if required.
Pour enough batter into the waffle maker to just cover the waffle grids (typically about 1/2 to 3/4 cup, depending on waffle maker size). Close the lid and cook for about 3-5 minutes or until golden brown and crispy.
While the waffles are cooking, melt the butter in a shallow bowl. In another bowl, mix the remaining sugar with an additional teaspoon of cinnamon for the coating.
Once the waffles are done, carefully remove them from the waffle maker. Cut each waffle into strips to create the sticks.
Immediately dip each churro stick into the melted butter, ensuring they are well coated. Then roll them in the cinnamon-sugar mixture until fully covered.
Serve warm with chocolate sauce or caramel sauce on the side for dipping.