Saute onions and mushrooms in margarine. Remove from heat. Add parsley, eggs, cheeses and seasoning. Combine well. Trim crusts from bread and cut into 4 equal squares. Roll pieces flat with a rolling pin. Dip bread in melted butter and arrange in miniture muffin tins. Fill each with mushroom-cheese mixture. Bake 180ºC or 20-25 minutes.