Combine 1/2 cup of white sugar with the cinnamon on a plate. Set aside and line another plate with paper towels.
In a small saucepan over medium heat, whisk together the water, 1 1/2 tablespoons sugar, salt and 2 tablespoons vegetable oil. Bring the mixture to a boil then remove it from the heat. Stir in the flour, mixing until it forms a smooth ball.
Heat 3 to 4 inches of vegetable oil in a large, heavy-bottomed pot set over medium-high heat until it reaches 375ºF.
Transfer the dough to a cloth pastry bag fitted with a large star tip and pipe the dough over the pot of oil to a length of about 4 inches, then using scissors or a sharp knife, cut it so it releases into the oil. Pipe two to three churros into the oil at a time, frying them until they're golden brown and cooked through. Transfer the churros to the paper towel-lined plate to drain for 2 minutes. Then roll them in the cinnamon-sugar mixture. Repeat the frying and coating process with the remaining dough.
Serve the churros with the warm chocolate sauce (recipe below) and the dulce de leche which can be bought from the store.