Preheat oven to 350F. Grease a 9x13-inch baking pan.
Add the ground beef and onions to a skillet. Cook over medium heat until the ground beef is cooked through.
Stir the spaghetti sauce into the ground beef. Mix well.
Combine the ricotta cheese and mozzarella cheese in a small bowl. Mix well.
Place the rice in a medium bowl. Add the eggs to the rice and use a fork to mix the eggs and rice together. Sprinkle the onion powder and garlic powder over the rice mixture. Stir to combine thoroughly.
Spread 1/3 of the meat sauce to the bottom of the casserole dish.
Then spread 1/2 of rice on top of the sauce.
Spoon 1/2 of ricotta cheese mixture on top of the rice.
Repeat the layers. Then spread the remaining 1/3 of the meat sauce on top.
Sprinkle with the grated Parmesan cheese.
Bake at 350 degrees for 25 - 30 minutes or until the cheese is thoroughly melted. Let stand for 5 minutes before serving.