baked spaghetti casserole

Ingredients For baked spaghetti casserole

• 1 c

  onion, chopped
• 1 c

  green pepper, chopped
• 1 Tbsp

  butter or margarine (i used nonstick cooking spray)
• 2 (14 oz.) can

  diced tomatoes, undrained
• 1 (4 oz.) can

  mushroom stems and pieces, drained
• 1 can

  (2.25 oz.) sliced ripe olives, drained
• 2 tsp

  dried oregano
• 1 lb

  ground beef, browned and drained* (see my notes)
• 12 oz

  spaghetti, cooked and drained according to package directions
• 2 c

  (8 oz.) shredded cheddar cheese
• 1 can

  (10.25 oz.) condensed cream of mushroom soup
• 1/4 c

  water
• 1/4 c

  grated parmesan cheese