Drain spinach and squeeze out excess liquid (substitute frozen chopped spinach, thawed , if desired).If using fresh spinach, wash thoroughly and tear leaves into bite-size pieces.
Wilt spinach in a covered pan (adding no extra water).
Combine the spinach with the beaten eggs, milk, cheese, bread crumbs, onions, and Parmesan cheese.
Turn mixture into a greased 1 quart baking dish.Cover and bake at 375 degrees for 25 to 30 minutes or until done.