In a medium saucepan, bring the water, butter, salt & sugar to a boil.
Once it starts boiling, remove from the heat and quicky whisk in the cup of flour. Once it's all combined, shake the dough out of the whisk and switch to a rubber spatula.
Place the pan back over a medium-low heat and stir the smooth dough ball continuously over the heat until a thin film coats the bottom of the pan. (refer to picture)
Remove from the heat and transfer the dough to the bowl of a stand mixer or a large bowl if using a handheld mixer. Let the dowl sit about 10 minutes to cool a bit.
Then using the paddle attachment or beaters, begin to beat the dough, adding the eggs one at a time, letting them combine completely before adding the next. Once both eggs are added let it mix on medium speed for a couple minutes until smooth and silky.
While the dough is mixing, begin heating the oil in a medium/ large saucepan. (Use enough so it goes up sides to almost half of the pan, about 4 inches.) Heat the oil to between 350/370F or 180/190C.
When the dough is finished, transfer it to a piping bag (this is the best choice, but in a pinch, a doubled plastic zip-top bag might work, but they tend to bust) fitted with a large star tip (I use Ateco 846.)
Once the oil is hot enough, snip off the end of the piping bag and begin piping the churro dough directly into the hot oil, using a kitchen shears to cut them once they are 6" long. Add a few more to the pot, but do not overcrowd the oil.
Fry the churros for about 2 minutes per side, flipping them once the bottom side is golden brown. Then place them on a paper towel lined plate to dry slightly.
Then while still warm, roll them carefully in the cinnamon sugar to coat both sides.
Repeat with the rest of the dough, making sure the oil is still hot enough between batches.
Serve warm as is or with the Mexican Chocolate Dipping Sauce.
Place the 2 chopped chocolates in a medium bowl. Heat up the cream to simmering, then pour over the chocolate. Let sit for a minute, add in the salt and stir until smooth.
*Make Ahead- the churro dough can be made a day or two in advance, and stored wrapped tightly in plastic or in the piping bag in the refrigertator. Place at room temperature 30 minutes to an hour before using
*Don't have a star tip? Just cut a smallish tip of the pastry bag. They just won't have that classic lined shape.
*Don't have a thermometer to check the oil? You can drop a small amount of dough in the heated oil.... If the oil starts to bubble steadily, then the temperature is ready. If it bubbles too vigorously, then the oil is too hot. Turn down the heat a bit.