To make the crullers: In a medium saucepan
, heat 1 cup water, the butter, sugar, vanilla, and salt over medium-high heat until the edges of the liquid start to bubble. Add the flour all at once and stir briskly with a wooden spoon until well mixed and no lumps of flour remain.
Remove from the heat. Add 4 of the eggs
, 1 at a time, beating well with a wooden spoon after each. The dough should look soft and glossy and keep a "hook" shape when the spoon is pulled from the dough
. If not, beat in the last egg.
Scrape the dough into a pastry bag
fitted with a star tip. Pour enough canola oil
into a deep heavy skillet (cast iron is ideal) to fill 1-inch. Heat over medium heat until the tip of the handle of a wooden spoon gives off a slow steady stream of tiny bubbles. Carefully pipe the dough into the oil, forming 6-inch crullers. Pipe only as many crullers into the oil as fit comfortably. Overcrowding the pan will result in soggy crullers. Fry
, turning once, until golden brown on each side. Drain
on paper towels. Repeat with the remaining dough.
Put the sugar and the cinnamon in a paper bag. Crimp the top and shake well to mix. Drop a few crullers at a time into the bag and shake until coated. Best served as soon as possible.