In a large mixing bowl, combine the ground beef, breadcrumbs, Parmesan cheese, beaten egg, minced garlic, dried oregano, salt, and black pepper. Mix well.
Form the mixture into small meatballs, about 1 inch in diameter.
In a baking dish, spread the meatballs evenly. Pour the chicken broth over the meatballs.
Sprinkle the chopped spinach over the meatballs and broth.
Evenly distribute the orzo pasta over the top.
Cover the baking dish with aluminum foil and bake for 30 minutes.
Remove the foil and bake for an additional 10 minutes, or until the meatballs are cooked through and the orzo is tender.
Let the casserole rest for a few minutes before serving.
Notes:
This casserole is a great way to enjoy the flavors of Italian wedding soup in a hearty, comforting dish.