In a bowl, whisk together the sugar and cinnamon. Set aside.

In a saucepan, combine the milk, water, butter, vanilla, sugar, and salt. Heat over medium heat until the mixture starts simmering and the butter has melted. Remove from the heat and add the flour all at once. Mix with a rubber spatula until no dry ingredients are left.

Bring the saucepan back to the heat and cook the dough for 1-2 minutes, mixing continuously with the rubber spatula until a whitish film forms on the bottom of the pan and the dough forms a ball with a homogeneous consistency. Remove from the heat.

Gradually add the eggs, beating on medium speed until fully incorporated. Scrape the sides and the bottom of the bowl and beat one last time just for a few seconds to mix. The dough should be smooth and shiny. It should be firm enough to hold a shape when piped out but moist. If this texture is achieved before all eggs are incorporated, stop adding them. If the texture is not there yet after you’ve added all the eggs, you need to add ¼ - ½ extra egg.

Transfer the dough into a piping bag fitted with an open star nozzle (such as Wilton 1M).

Heat approximately 2” (4cm) of oil in a pot over medium-high heat to 360F - 370F (180C - 190C).

Pipe 5”- 6” (12cm-15cm) lengths of dough directly into the hot oil, using scissors to cut the dough at the nozzle tip.

Fry the churros in batches, avoiding overcrowding the pot for 3-4 minutes or until golden brown on each side.

Remove the churros with a slotted spoon or tongs and place them on paper towels to drain excess oil and cool down.

While still warm, roll the churros in the cinnamon sugar mixture to coat. Serve immediately with your favorite dipping sauce, such as chocolate or dulce de leche.