Moisten the matzos in hot water. Drain well. In a large bowl, beat the eggs, salt, nutmeg and pepper. Gently fold the matzo into the egg mixture. Heat the butter in a large skillet and saute the onions. Add the mushrooms and saute until soft, 3 to 4 minutes. Pour the egg mixture into skillet. Seaon to taste with salt and pepper. Brown on one side, shaking the pan to avoid sticking. Turn and brown on the other side. Serve hot, with preserves or honey.