Salisbury Steak Meatballs

Instructions

1. In a large nonstick skillet, melt the butter over medium heat. Add the onions and cook until softened, about 5 minutes. Add the mushrooms, turn the heat up to medium-high, and cook for an additional 5 minutes.
2. For the meatballs, in a medium bowl, add ground beef, breadcrumbs, milk, parsley, Parmesan cheese, salt, and pepper. Gently mix to combine. Roll the mixture into 24 meatballs (see notes).
3. Move the mushrooms and onions to the sides of the skillet and add the meatballs. Cook, turning occasionally, until browned on the outside. If your skillet is smaller than 12-inches, transfer the mushrooms and onions to a bowl and brown the meatballs in batches as needed.
4. Meanwhile in a small mixing bowl, whisk together the ingredients for the sauce. Pour sauce over the meatballs.
5. Bring the mixture to a boil, reduce the heat to a simmer, and cook, uncovered, for 10 minutes.
6. Cover with a lid and simmer for an additional 12 to 20 minutes or until the meatballs are cooked through and reach 160°F.