For the chocolate sauce, boil 125 ml water, 125 g sugar and 1 pinch of salt in a pot. Stir in 100 g of cocoa with a whisk, simmer for 3-4 minutes while stirring. Set aside, stir from time to time.
For the churros, put flour in a bowl. Bring 500 ml water, 75 ml oil and 1/2 teaspoon salt to the boil briefly. Pour over the flour and immediately knead into a smooth dough with the dough hooks of the hand mixer.
Heat the oil to approx. 180 °C for frying. Pour the dough in portions into a piping bag with a large star-shaped spout. Carefully pour the dough directly into the hot oil in approx. 10 cm long strands. Bake for about 5 minutes until golden brown.
Remove with a skimmer and drain well on kitchen paper. Mix 150 g sugar and 1 tablespoon cocoa powder. Turn churros in cocoa sugar. Serve with chocolate sauce.