In a large skillet, brown beef over medium heat until no longer pink; cut up any remaining chunks of beef and reserve.
In a large saucepan, combine whole tomatoes and paste; mash until smooth. Cover and heat on low.
In a large skillet over medium heat, quickly sear onion and celery until transparent; add to tomato sauce in saucepan. In same skillet, saute bell peppers and mushrooms for a few minutes, but do not allow them to become soft; add to tomato sauce.
Add Italian seasoning, dried red pepper flakes, bay leaves, basil and garlic to tomato sauce; add beef and mix. Remove cover, simmer over low heat and continue to simmer all day, stirring occasionally.
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.
