Make the Churro Dough: In a medium saucepan, combine the water, butter, 2 tablespoons of sugar, and salt. Bring the mixture to a rolling boil over medium-high heat.
Add the Flour: Once boiling, remove from heat. Immediately add the flour all at once and stir vigorously until a smooth dough forms.
Cool Slightly and Add Eggs: Let the dough cool for 5-7 minutes. Add eggs one at a time, mixing well after each addition until smooth and glossy.
Prepare for Frying: Heat 2-3 inches of vegetable oil to 350°F (175°C) in a large pot.
Pipe the Churros: Transfer dough to a piping bag with a star tip. Pipe 4-6 inch strips into hot oil, cutting with scissors. Fry in batches.
Fry Until Golden Brown: Fry churros for 2-3 minutes per side until golden brown and crispy.
Drain and Coat in Cinnamon Sugar: Drain churros on paper towels. While warm, toss in cinnamon-sugar mixture.
Make the Chocolate Sauce: Melt chocolate, heavy cream, and butter together until smooth. Stir in vanilla extract.
Serve and Enjoy: Serve warm churros immediately with chocolate sauce for dipping.