XOCO Churros with Mexican Hot Chocolate

In a small bowl, whisk together the sugar and cinnamon. DO AHEAD: The cinnamon sugar can be made ahead and stored, in an airtight container at room temperature, up to 1 month.

In a heavy 2-quart saucepan over moderate heat, combine the milk or water and the chocolate.

Heat, stirring occasionally, until the chocolate is almost completely dissolved (there will still be small pieces of chocolate) and the mixture is steaming.

Transfer to a blender or use a handheld immersion blender and process until the mixture is foamy and fully emulsified, about 30 seconds (use caution when blending hot liquids). Return the hot chocolate to the saucepan. When ready to serve, place over low heat, stirring occasionally, until warm.

In a medium pot over moderate heat, whisk together the butter, sugar, salt, and 1 1/4 cups water. Bring to a simmer, stirring to melt the butter.

Remove the pot from the heat and add the flour, stirring vigorously to fully incorporate it into the liquid. Return the pot to moderate heat and cook the mixture, stirring constantly, until the dough is smooth and sticky, about 1 minute. Turn off the heat and remove the pot from the burner; cover with a lid or plastic wrap, and let rest for 15 minutes.

Following the 15-minute resting period, add the eggs, 1 at a time, stirring with a wooden spoon until completely incorporated after each addition. Spoon the dough into a pastry bag fitted with a 1/2-inch star tip.

Line a large baking sheet with several layers of paper towels and place the cinnamon sugar in a small shallow bowl.

In a heavy large pot, heat 3 inches of oil until a deep-fat thermometer registers 375°F. Working in batches (about 6 churros per batch), hold the pastry bag just above the surface of the hot oil and carefully and gently pipe 4-inch ribbons of dough directly into the oil, using a paring knife to cut the batter at the end of the star tip if necessary. Fry the churros, turning occasionally, until golden brown and cooked in the center, about 2 minutes per batch.

Transfer as done to the paper-towel-lined baking sheet and return the oil to 375°F between batches. Toss the churros in cinnamon sugar and serve warm with the Mexican hot chocolate.