Boil 1 cup (250 ml) water with the butter and sugar. Pour in the flour all at once and mix until you have a smooth dough. Remove from the heat soon as it begins to separate from the dish.
Add the eggs one at a time to the cooled dough, stirring constantly.
In a deep dish, heat the oil. Spoon the dough and drop it in the oil. Fry until golden and while still warm, sprinkle the eclairs with powdered vanilla sugar thoroughly.
Optionally, once cooled, you can top the fried eclairs with a chocolate topping or hot syrup prepared from 1 cup (250 g) of granulated sugar and 1 cup (250 ml) water, boiled for 3-4 minutes.