In a large pot with boiling salted water, cook pasta until al dente. Drain well.
Meanwhile, in a blender or food processor puree roasted red capsicums, tofu, tomato paste, vegetable stock, balsamic vinegar and Italian herbs. Set aside.
Coat a medium saute pan with cooking spray. Cook onion, garlic and asparagus over medium heat until tender, about 5 minutes. Add water if necessary to prevent sticking. Stir in mushrooms; cook 3 to 5 minutes, or until mushrooms are tender and soft. Stir in tofu sauce, tomatoes, black pepper. Add hot chilli paste, if desired. Reduce heat to low and heat through.
Toss pasta with sauce, and serve with Parmesan cheese.