Begin by taking a large pot and adding about an inch deep of cooking oil to it. Set the heat to medium. The temp should be between 350 F and 375 F
In a medium pot, combine the water, butter, and salt. Set the burner temp to medium and heat the mixture until the butter melts and it starts to boil.
Pour in all of the gluten-free 1 to 1 four mix and stir really quickly, eventually, a dough will form. Keep stirring and pushing down on the dough, for about a minute. Now remove it from the heat.
Add the hot gluten-free churro dough to a bowl. Stir the dough until it cools down and is just barely warm but not hot anymore. It will take 5 to 10 minutes.
Once the dough has cooled, add the egg. Start stirring again. At first, it will seem like the egg doesn't want to mix in with the dough, but eventually, it will.
Add the pastry tip to a piping bag. Now fill up the bag with the gluten-free churros dough.
Pipe the dough and allow it to gently go into the hot oil. Use your finger to separate it from the pastry tip or you can also snip it with kitchen shears.Allow the churros to cook for 5 to 8 minutes, turning them with tongs or a spider ladle. This will make sure they evenly brown. Once they are lightly golden brown they are ready to be taken out. Place them on a paper towel to dry.
Mix together the cinnamon and sugar and put it on a pie plate or something like that. Then roll those gluten-free churros in the cinnamon and sugar. Enjoy!