In a shallow dish, mix together the cinnamon, salt and sugars. Set aside.
In a saucepan over medium heat, add the water, butter, sugar, salt, and vanilla. Stir until butter is melted and ingredients are combined. Sift in the flour and stir until a dough ball forms. Remove from heat. Place dough into the bowl of a stand-mixer and allow to cool for 5 minutes.
Set a large, heavy-bottomed pot (I used my dutch oven), filled with 2 inches of oil over medium-high heat.
Using the paddle attachment, beat in eggs, one at a time, to the dough. Scoop batter into a large piping bag fitted with the large star tip.
When the oil is good and hot (350-375 degrees), pipe churros (I made mine about 6 inches long, but the length is your preference) into pot in batches of 4 at a time (or as many as fit well in the pan without crowding according to size).
Fry until golden brown and crisp on bottom (mine took 60-90 seconds each side), then flip. Drain fried churros on paper towels and dip directly into cinnamon sugar mixture while still hot. Repeat process until all the batter has been used.
*I kept my churros warm in a 200 oven in a single layer on a baking sheet in the oven while I fried the rest.