In a large bowl, combine and mix hash browns with mashed potatoes. Add melted butter, onion, salt, pepper, eggs and milk. Mix well.
Heat 2 tablespoons olive oil until hot in an 8 or 10-inch nonstick skillet. Ladle 1/2 cup measure of potato mixture into it, swirling pan to distribute a pancake that covers the entire bottom of pan and comes up the sides slightly. Cook 2 minutes or until very well browned. With a long spatula, turn pancake and cook 2 more minutes. Turn back to first side and cook another few seconds. Transfer to a paper towel-lined large plate. Roll and keep warm in a 200 degree oven until all are cooked. *.
Continue cooking potato mixture in skillet until all is used, rolling each and adding to platter in the oven to keep warm.
Meanwhile, in a saucepan over low heat combine green onions, spinach, Alfredo sauce and parsley. Mix well, cover and gently warm. Serve 2 rolled pancakes per serving, topping each with spoonfuls of spinach sauce.
* Pancakes may be cooked two at a time on a two-burner stove-top griddle.