Combine castor sugar & cinnamon powder in a shallow bowl & mix well to make the cinnamon sugar coating & set aside.
¼ cup castor sugar, ½ teaspoon cinnamon powder
Take 2 large piping bags & insert star nozzle & cut an end so that the nozzle pops out.
Use a large tall glass & insert two piping bags into it, open the piping bags & fold them over the rim of the glass.
Heat a pot, add water, butter, salt, sugar & vanilla essence, stir well & boil it on high.
1 cup water, 3 tablespoons unsalted butter, 1 tablespoon sugar, ½ teaspoon vanilla essence, A pinch of salt
As soon as the water boils, switch off the heat, add maida, stir well using a spatula & form a dough. The dough will be thick & gummy.
1 cup maida
Let the dough rest for 1-2 minutes or until it gets warm to touch.
Transfer the dough to the piping bag & push the dough down, seal the open end of the piping bag by twisting it.
Take a deep pan or kadai with one and a half inches of oil for frying. Once the oil is medium hot, start piping 3-4 inches long churros into the oil & cut the ends using a knife. See note 2
Oil for deep frying
Fry the churros for 2-3 minutes on medium heat rolling occasionally. When they turn crisp & golden, transfer them onto a sieve so that all excess oil drips off.
The oil should be medium hot which ensures even frying of churros. Fry only 5-6 churros in a batch to avoid overcrowding the pan.
While the churros are still hot, roll them in cinnamon sugar & serve.