Baked Spaghetti

Ingredients

• 1 c. chopped onion
• 1 c. chopped green pepper
• 1 Tbsp. butter or margarine
• 1 (28 oz.) can tomatoes with liquid, cut up
• 1 (4 oz.) can mushrooms (stems and pieces), drained
• 2 tsp. dried oregano
• 1 lb. ground beef, browned and drained
• 12 oz. spaghetti, cooked and drained
• 2 c. (8 oz.) shredded Cheddar cheese
• 1 (10 3/4 oz.) can condensed cream of mushroom soup
• 1/4 c. water
• 1/4 c. Parmesan cheese