Preheat oven to 350. Coat a 2 quart square baking dish with cooking spray. Spread potatoes evenly in bottom of prepared baking dish. Sprinkle with ham, cheese and green onions
In medium bowl, mix eggs, milk, salt and pepper. Pour egg mixture over potato mixture in dish.
Bake uncovered for 40 to 45 minutes or til knife inserted near center comes out clean. let stand for 5 minutes before serving. To make a double batch of this, Prepare as above, but double all ingredients and use a 3 quart rectangular baking dish. Bake uncovered for 45 to 55 minutes or til a knife inserted near center comes out clean. let stand for 5 minutes before serving. Serves 12