Special equipment: Piping bag fitted with a large star decorating tip
Make the dough by heating water, sugar and salt in saucepan over medium heat until hot. Add the flour all at once and stir vigorously for 1 minute on the heat to dry the mixture out. Remove from heat and transfer the dough to a stand mixer bowl; mix on low speed until there is no longer steam escaping from the dough. With the mixer running on medium, add the eggs, 1 at a time, incorporating completely until a shiny, smooth texture forms before adding the next egg, and then the egg yolk. Scrape down the mixer bowl with a rubber spatula between each addition. Transfer the dough to the piping bag.
Pour oil into a large heavy bottomed pot to a depth of 4 inches; heat over medium-high heat to 375 degrees F.
To fry the churros, carefully squeeze the dough from the piping bag directly over the oil in 3 to 4-inch lengths, cutting the dough at the tip with a butter knife and gently dropping them into the oil. Turn frequently with a Chinese strainer or tongs until golden brown, about 3 minutes. Work in batches to prevent overcrowding the pan and allowing the oil to reheat to 375 degrees F between each batch. Drain the churros on a paper towels and then toss in sugar to coat while still warm.
Melt the chocolate in a glass bowl set over a pan of barely simmering water. Arrange the curros on a serving platter and serve the chocolate sauce alongside. Enjoy!
Cook's Note: Self-rising flour makes the churros a bit lighter and fluffier, but all-purpose flour works just fine. Pick your favorite flavored chocolate; I love the flavor of orange and chocolate or even bacon chocolate with these churros!