Bring A Large Pot Of Lightly Salted Water To A Boil. Add Pasta And Cook For 8 To 10 Minutes Or Until Al Dente; Drain. In Same Pot, Saute Onion And Bell Pepper Over Medium Heat Until Softened. Remove From Pan. In Same Pot, Cook Sausage Over Medium Heat Until Brown. Drain. Combine Onion Mixture, Pasta, Sausage, Mushrooms And Stewed Tomatoes In Same Pot And Heat Through, 5 Minutes. Serve.