creamy ground beef casserole

Ingredients For creamy ground beef casserole

• 1 1/2 lb

  ground beef
• 1/2 tsp

  garlic powder
• 1/2 tsp

  salt
• 4-1/2 c

  spaghetti sauce
• 1-1/2 c

  sour cream
• 1 c

  chopped onions
• 1/2 lb

  wide noodles, cooked
• 2-1/2 c

  grated monterey jack cheese, divided
• 1 c

  canned sliced mushrooms
• 1/4 c

  grated parmesan cheese
• 1

  large egg. slightly beaten
• 2-1/2 c

  grated parmesan cheese
• 1-1/2 c

  grated monterey jack cheese
• 1 pkg

  {10 ounce} frozen spinach, thawed and well drained
• 1/3 c

  chopped green onion