Preheat oven to 350.
Brown the 1 1/2 lb ground chuck and 3 tbsp onion.
Drain off the fat and return to the skillet.
Add the 1/4 tsp garlic powder and 24 oz of spaghetti sauce.
Microwave the 8 oz cream cheese for 60 seconds.
Sir the cream cheese until creamy.
Mix the egg and 1/4 tsp black pepper into the cream cheese.
Mix the 3 cups spinach into the cream cheese.
Spread half the meat mixture into the 8 x 8 glass dish.
Spread all the spinach mixture into the dish.
Spread 8 oz of mozzarella cheese into the dish.
Spread the remaining meat mixture into the dish.
Spread the 4 oz parmesan cheese into the dish.
Bake for 30 minutes.