Brown ground beef in a skillet over medium-high heat; drain. Add tomatoes, sauce, green pepper, mushrooms, garlic, salt, sugar, and broth; cover and simmer over low heat for 10 minutes.

In a medium bowl, blend together cream cheese, sour cream, onion and one cup Cheddar cheese; set aside.

In an ungreased 13" x 9" inch baking pan, layer half the beef mixture, half the noodles and half the cheese mixture; repeat layers. Top with remaining Cheddar cheese. Bake, uncovered, at 350 degrees F. for 40 minutes.