If you assume that food trucks are a modern concept, think again. The only thing that’s “new” is the truck part. Humans used to be the vehicles for street food, so the whole idea had legs well before it had fuel-powered wheels.

Tan tan refers to an across-the-shoulder pole carried by food peddlers in old Sichuan. Baskets—one with sauce and the other with noodles—dangled from each end of the pole, providing an inexpensive and nourishing meal to strolling locals. Eventually the noodles were named after the pole, coming to be known as "peddler's noodles.”

The traditional, original Chinese recipe is a chili-laced noodle soup strewn with ground pork, preserved vegetables, and scallions. My own version combines minced vegetables and tofu with a black bean-chili-garlic-peanut butter sauce to make a ground meat-like hash that coats the noodles with deep, dark essence and crunch.

• You can get the rest of the recipe going while waiting for the noodle water to boil.

• Make sure you use a large-enough, deep-enough pan to house the volume of this dish.

• I alternate between Lee Kum Kee Black Bean-Garlic Sauce and Chili Black Bean Sauce for his recipe, as they both work very well. You can also use a plain chili paste or any chili-garlic sauce.

• Use the least-processed, freshest-tasting peanut butter you can find. The salt measurement in the recipe is based on the creamy, lightly salted variety I use in my own kitchen. So keep that in mind if you are making the recipe with unsalted peanut butter, and adjust the seasoning accordingly.

• Almond butter can be swapped in for the peanut butter.

• Use the firmest firm tofu you can find. If you have any doubts, you can firm it up further by boiling it, already diced, for about 10 minutes well ahead of time. Drain and dry it thoroughly before adding to the stir-fry.

1. Combine the peanut butter, black bean-garlic sauce or chili sauce, sweetener, and hot water in a medium-large bowl and whisk until blended. Set it near the stove.
2. Put up a large pot of water to boil, and set a colander in the sink.
3. Meanwhile, place a large (10- to 12-inch) skillet or a large wok over medium heat and wait about a minute. Add the oil, swirl to coat the pan, and then toss in the onion, and sauté for about 2 minutes, or until the onion begins to soften. Add the shiitakes and a big pinch of salt, and cook, stirring, for another 3 minutes or so to brown. Add the celery, water chestnuts, and tofu.
4. Keep the heat medium-high as you cook and stir, allowing the mixture to stick to the pan a little and brown. Use a spatula with a thin metal blade to scrape the bottom of the pan, so the well-done bits can become incorporated. (You can add a touch more oil during this time—moving things over so it hits the pan directly.) Keep this process going longer than you think —up to 5 minutes or so—until the vegetables and tofu are deeply browned.  Keep scraping as you go.
5. Turn the heat to low, and pour in the peanut sauce, scraping the bowl to make sure you include every last bit.
6.  When the water boils, add the noodles, and cook until done to your liking. Drain them thoroughly in the colander, and transfer them to the pan of sauce.  Toss to coat and serve immediately.