Cook fettuccine according to package directions. Meanwhile, in a large saucepan, bring 3/4 cup broth to a boil. Add the zucchini, yellow squash, broccoli, red pepper, carrot, onion, basil and salt. Return to a boil. Reduce heat; cover and simmer for 6-8 minutes or until vegetables are crisp-tender.
In a small bowl, combine cornstarch and remaining broth until smooth; stir into vegetable mixture. Bring to a boil; cook and stir for 2 minutes or until slightly thickened. Remove from the heat; stir in tomatoes and sour cream.
Drain fettuccine; place in a large bowl. Add the vegetable mixture, cheese and parsley; toss to coat.