01 -
Heat ½ of the olive oil in a large high-walled skillet over medium heat. Add the finely diced onion and garlic. Soften for 5 minutes, then set aside and let cool.
02 -
In a large bowl, combine breadcrumbs, Parmesan cheese, whisked egg, milk, cooled onion/garlic, salt, oregano, allspice, nutmeg, and pepper. Gently incorporate the meat without overworking it.
03 -
Roll into 1 ½-inch meatballs and place on a plate. Chill for 15 minutes or up to overnight. Cover if chilling overnight.
04 -
Combine beef broth, chicken bouillon, Worcestershire sauce, Dijon mustard, and parsley in a large measuring cup. Set aside.
05 -
Heat the remaining olive oil in a large skillet over medium-high heat. Brown meatballs in batches, leaving space for easy rotation. Brown for about 1 minute per side, then set aside.
06 -
Melt the butter in the same skillet over medium heat. Use a silicone spatula to clean the skillet bottom. Stir in the flour and cook for 2 minutes, stirring continuously.
07 -
Gradually add the beef broth mixture, stirring continuously. Bring to a boil, then reduce to a simmer. In a bowl, mix ¼ cup of sauce with sour cream, then stir the mixture back into the skillet over low heat.
08 -
Add meatballs back to the skillet along with any plate juices. Spoon sauce over them, cover partially, and simmer on low heat for 10-15 minutes or until cooked through.
09 -
Garnish with fresh parsley and serve over mashed potatoes or egg noodles.