Fill a large pot ¾ of the way with water, add 1 tsp of salt and 1 tbsp of olive oil. Bring to a rolling boil over high heat. Add pasta and cook as per directions or until pasta is al dente.
Meanwhile, heat olive oil in a large frying pan or wok. Add the onion, garlic and chili (if using) along with a pinch of salt and sauté until the onion has almost softened.
Add the mushroom and continue to sauté until these have softened. Stir in tofu, peanut butter, nuts, soya sauce, maple syrup and 4 tbsp of pasta water until the sauce thickens, adding a little more water if needed to get the sauce consistency you’d prefer.
Add the pasta and tossing while still on the heat to coat and combine before serving.
Divide into serving bowls. Garnish with green onions.