Prep your cinnamon and sugar, and place in a flat bottomed dish so that it's "ready and waiting" to coat the Churros once they're fried!
Pour a generous amount of sunflower oil into a large frying pan (filling about 2cm deep). Place it onto a stovetop, on a medium heat. Allow the oil to heat up while you mix the batter, but keep an eye on it because oil should never be left unattended on a stovetop!
Add the water, milk, butter, sugar, and salt into a medium sized pot. Place it onto a stovetop, on a medium heat, stirring occasionally until the butter melts.
As soon as the butter has melted, add the flour and give it a sir with a fork until a dough forms. It takes really quick, and don’t worry if there are any lumps at this point. Remove it from the stove and allow to cool slightly for about 2 or 3 minutes.
Once slightly cooled, add the egg and vanilla essence, and immediately beat it with an electric mixer until combined. Make sure to beat it as quick as you can, otherwise the egg could start cooking when it's added!
Transfer the dough into a piping bag, and use a big star piping tip (with at least 8 points). Make sure to use a heavy duty piping bag as the dough is quite thick, and places a lot of pressure on the bag, sometimes splitting thin disposable plastic piping bags!