Cook noodles in a large pot of boiling water until al dente. Drain.
Meanwhile, mix together tahini, lemon juice, and water until smooth. Add garlic, yogurt, and pepper sauce.
In a medium skillet, heat oil over medium high heat. Saute red pepper and zucchini in oil for 2 to 3 minutes, or until tender crisp. Add tahini sauce, and heat through. Season to taste with salt and pepper. Do not boil or overcook: this sauce curdles easily. Toss noodles with sauce.
