Thinly slice the mushrooms, carrot, kohlrabi, and fried tofu. Cut the vegetables into bite-sized pieces. Sauté garlic, then add carrot and kohlrabi and stir-fry until softened. Add the mushrooms next.

Blanch the egg noodles briefly, then drain well. Add the noodles to the pan with the vegetables and toss to combine. In a small bowl, mix 2 tablespoons vegetarian oyster sauce, 1 tablespoon soy sauce, 2 teaspoons vegetarian bouillon powder, 1 tablespoon sugar, and 1 tablespoon sesame oil. Pour the sauce into the pan and toss the noodles to coat evenly. Add the baby bok choy last.