Cook spaghetti according to package directions, rinse and drain.
Combine ground beef, eggs, panko, soy sauce and 1/2 cup Parmesan cheese and 2 cloves of garlic in a large bowl; shape into 11/2-inchsized meatballs. Bake the meatballs at 350° on an ungreased cookie sheet for 10-12 minutes. Meanwhile, heat a deep skillet, add the oil, garlic and onions and sauté for about 5 minutes until the onions are soft. Add tomatoes and the remaining garlic, cheese and oregano.