Martha's recipe is inspired by one she tasted from Naomi Duguid and Jeffery Alford, authors of Hot Sour Salty Sweet: A Culinary Journey Through Southeast Asia.
Toss pork with sugar in a small bowl to mix. Combine tamarind concentrate, soy sauce, and fish sauce in another small bowl.
Preheat a 14-inch carbon-steel wok over medium-high heat until very hot. Add 2 tablespoons oil and swirl to coat sides and bottom. Cook garlic, turning over with a wooden spoon until golden, about 15 seconds.
Add pork, spreading into a single layer and cook until golden on all sides, about 1 minute. Add tofu and sear, pressing it against the sides of the wok, 10 to 20 seconds. Remove to a plate; set aside.
Season eggs with salt and pour into wok. Cook until the eggs start to set, about 1 minute. Using a spatula, cut into large pieces, and transfer to a shallow bowl or plate.
While meat rests, reheat wok over medium-high heat until sizzling-hot. Add 1 tablespoon oil and swirl to coat sides and bottom. Cook noodles, tossing and turning often and pressing against the sides of the wok to sear, until softened, about 2 to 3 minutes.
Push noodles up sides of wok and add remaining 1 tablespoon oil to bottom of wok and 2 to 2 1/2 cups bean sprouts and the scallions. Cook, tossing and turning, until wilted, about 20 seconds. Add dried shrimp and toss briefly with spatula. Add soy-sauce mixture. Cook, tossing and turning, about 30 seconds. Incorporate noodles. Transfer pork mixture to wok along with 1/2 cup peanuts and egg; toss gently to combine.
Divide among bowls and sprinkle with cilantro to serve. Remaining bean sprouts, additional peanuts, and other condiments should be served on the side.
