Mix cinnamon and sugar in a shallow dish. Set aside for coating.
In a bowl, combine flour, baking powder, and salt. Add oil and boiling water. Stir until a thick, sticky dough forms.
Transfer dough to a piping bag fitted with an 8mm star tip. Let rest while oil heats.
Heat 2 inches of oil in a pot to 170°C (340°F). Use a thermometer or test with a bread cube—it should brown in 20 seconds.
Pipe 6-inch strips directly into hot oil, cutting with scissors as you go. Fry 2–3 minutes, turning occasionally, until golden brown.
Drain on paper towels. While hot, roll churros in the cinnamon sugar mixture.
Make the chocolate sauce: combine chocolate chips and cream in a heatproof bowl. Microwave in 30-second bursts, stirring until smooth. Let cool slightly to thicken.
Serve churros warm with chocolate dipping sauce.
