1Melt 2 tbsp butter in a large skillet over low heat. Add the onions and a pinch of salt. Cook until caramelized, stirring occasionally.
2Combine the ground beef, egg, 1/2 cup Parmesan, breadcrumbs, garlic, parsley, Worcestershire sauce, half of the caramelized onions, salt, and pepper. Mix until combined, then form into meatballs.
3Heat 1 tbsp olive oil in the same skillet over medium heat. Sear the meatballs until browned.
4Remove meatballs from the skillet and set aside.
5Add the remaining caramelized onions and white wine to the skillet, scraping up the browned bits.
6Add the beef broth and bring to a simmer. Stir in the cornstarch slurry.
7Return the meatballs to the skillet and simmer.
8Combine the orzo and chicken broth in a separate pan. Bring to a boil, reduce to medium heat, and cook until the liquid is absorbed.
9Stir 1 tbsp butter, heavy cream, and 1/4 cup Parmesan into the orzo. Season with garlic powder, salt, and pepper to taste.
10Serve the meatballs and onion sauce over the creamy orzo. Top with chopped parsley.