dan dan mian
Dan Dan Mian has a billion versions. Tawainese have their versions. Sichuan has their versions. Generic Cantonese-Chinese has a version.
I prefer the Sichuanese ones. The best Sichuanese restaurants in the Bay Area will have a decent version. You can always ask for extra ground hua-jiao on top if that floats your boat.
Most szechuan places have it - but spell it Tan Tan noodles (listed on wikipedia as a normal different transliteration). China Village has it as the first noodle dish on their menu. Spices 3. Z&Y. Little Beijing on Noriega has it as "house special". Not hard to find.
369 12th St, Oakland, CA 94607
1316 Noriega St, San Francisco, CA 94122