Whisk flour, 1 tablespoon sugar, baking powder and salt in a medium bowl. Add vanilla, oil and water and mix with a spatula just until combined - don't overmix. It will be wet, thick and sticky.
Transfer dough into a pastry bag fitted with a large open star tip.
Add oil so it is 3-4 inches deep in a large deep sided skillet. Heat over medium heat to 350 degrees F. You may need to turn oil down to LOW if your stove runs hot (I heated my stove on medium then cooked on low).
Working in batches of three, pipe 4-6" lengths of dough into the hot oil, snipping with scissors at the end to release dough into the oil. Fry churros until golden, rotating a few times so the churros cook evenly.
Transfer churros to prepared paper-towel lined plate briefly to dab excess oil then immediately transfer to cinnamon and sugar and roll until evenly coated. Repeat with the remaining dough. Serve churros hot with Chocolate Sauce (recipe to follow).