Place water, olive oil, and salt in a saucepan and bring to a boil. Add the flour all at once and stir vigorously with a wooden spoon until a ball forms.
Cool slightly. Using a churro maker, press the dough out in 4 inch strips (which may be made in the shape of loops). The fluted shape is essential, otherwise the pastires will turn out hard and doughy.
Heat the frying oil, at least 1/2 inch deep, in a skillet until it is very hot. Reduce the heat to medium and fry the churros, turning once, until they barely begin to color. Do not fry more than 3 or 4 at a time, so that you can keep a watchful eye to prevent overcooking. Drain. Serve warm and dip in sugar.
These crunchy treats are great for breakfast or as a dessert. They are best served right away, but they can be frozen and reheated in a toaster.