Xi'an Biang Biang Noodles with Chili Oil

For biang biang noodles, start with the dough first. Sift the plain flour with the salt into a bowl, gradually pour in the lukewarm water, and stir until the mixture comes together into a rough dough.

Turn the dough out onto a floured surface and knead for about 10 minutes until smooth and elastic. Properly worked dough is firm, smooth, and stretches elastically when you pull on the ends without tearing. Cover it with a damp cloth and let it rest for 30 minutes so the gluten relaxes and the dough pulls more easily.

Divide the rested dough into 4 pieces, roll each into a thicker strip, brush with a little oil, cover again, and let relax for another 20 minutes. A longer rest makes the later pulling easier.

Meanwhile, prepare the sauce. Put the chili flakes, crushed Sichuan pepper, minced garlic, and the white parts of the scallions into a heatproof bowl.

Add the soy sauce, vinegar, and sugar. Bring salted water to a boil in a pot, and in a second saucepan heat the oil until it just begins to shimmer.

Take each dough strip by the ends and, by pulling and slapping it against the surface, stretch it into a long wide ribbon, then tear it open through the middle. Drop it into the boiling water and cook for 2 minutes.

Near the end, add the chopped pak choi to the pot and blanch together for the last 30 seconds, until the leaves soften and the stems stay crisp. Drain everything and immediately divide it into warmed bowls so the dish doesn't cool down.

Pile the prepared sauce onto the portions and carefully pour the smoking-hot oil directly over the spices, which will start to sizzle and release their aroma.

Stir the sauce together with the soy sauce and vinegar at the bottom of the bowl. Before eating, toss everything thoroughly so the noodles are coated in the aromatic sauce, and serve hot.