Combine ground meat, breadcrumbs, milk, parmesan cheese, eggs, onion, garlic powder, oregano, parsley, salt (about one teaspoon kosher salt or less for table salt), and ground pepper (to taste) in a large bowl.
With your hands, mix until evenly combined. Roll into balls about 2 inches in diameter (or any size, depending on your preference). Use a cookie scoop to make meatballs of equal size. Don't overmix or overpack the meatballs, as it will make them tough when cooked.
Set a sauté pan or a Dutch oven over medium heat. Add some oil and sear the meatballs until browned for about 3 minutes. Set them aside.
Set the same pan over medium heat, then add olive oil. Sauté onions, garlic, and crushed red pepper for about 2 minutes. Scrape the fond or browned bits off the bottom of the pan.
Add crushed tomatoes, oregano, sugar, bay leaves, some salt, and pepper to taste. Mix it and let it simmer.
Add the meatballs back into the sauce. Cover and simmer for about 20 minutes. Taste and adjust as needed.
Add parmesan cheese and fresh basil, as desired.
Serve over spaghetti or tapas-style with bread.