Boil the potatoes until tender, about 15 minutes, then drain. In a wok, fry the onions until crisp and golden, then repeat the process with the sliced garlic, tofu cubes, and wonton strips until everything is crunchy. Reserve 1 tablespoon of the frying oil.

Cook the wheat noodles in boiling water for about 4 minutes until tender, then rinse under cool water and drain well. For the sauce, soak the tamarind in hot water, strain it, and mix with sriracha, ginger, and sugar.

In a large bowl, combine the noodles, potatoes, cucumber, cabbage, and cilantro. Drizzle with the reserved onion oil and the tamarind sauce.

Fold in the fried onions, garlic, tofu, and wontons gently so they stay crisp, and serve the whole salad at room temperature.