Combine the peanut butter, gochujang, soy sauce, and hot water in a bowl and mix well to create the broth base.
Heat the olive oil in a pot over medium heat. Add the white parts of the green onions and a pinch of salt. Sauté for 1 minute.
Add the mushrooms and garlic and sauté for 2-3 minutes until fragrant.
Pour in the 1.5 cups of water and the sesame oil. Bring to a boil, then reduce heat and simmer for 5 minutes.
Add the noodles and cook according to package instructions.
For the crispy tofu crumbles, toss the crumbled tofu with the soy sauce and sesame oil.
Serve the noodle soup, topped with the crispy tofu crumbles and the green parts of the green onions.
