Suan la fen (酸辣粉, literally sour-spicy glass noodles) is a popular Sichuan street food dish — thick sweet potato glass noodles (红薯粉, hong shu fen) in a broth that is simultaneously sour (Chinkiang vinegar), spicy (chilli oil), numbing (Sichuan peppercorn), and deeply savoury. It is a simpler, more accessible relative of dan dan mian and reflects the Sichuan street food tradition of building complex flavour profiles in a single bowl.
The noodles: Thick sweet potato starch noodles (dried) — soak in cold water for 30 minutes, then boil until just cooked through (3-5 minutes). The sweet potato noodles have a distinctive chewiness and slight translucency that differs from mung bean glass noodles. The broth and sauce: In the serving bowl, combine: 2 tbsp chilli oil (with sediment), 1 tbsp Chinkiang vinegar, 1 tbsp soy sauce, 1 tsp sesame paste, 1/2 tsp Sichuan peppercorn oil, 1 tsp sugar, 1-2 tbsp hot noodle cooking water or broth to thin. The toppings: Fried peanuts (essential — their crunch provides textural contrast to the slippery noodles), ya cai (Yibin preserved mustard greens), fried soybeans, sliced scallion, fresh coriander, a drizzle of extra chilli oil.
Fuchsia Dunlop, Every Grain of Rice (2012); Fuchsia Dunlop, The Food of Sichuan (2019)