internal override NigiriSushi MakeNigiriSushi()
 {
     var ingredients = new List<string> { "Rice", "Red fish", "Wassaby" };
     var nigiriSushi = new NigiriSushi(ingredients, Name);
     return nigiriSushi;
 }
 internal override NigiriSushi MakeNigiriSushi()
 {
     var ingredients = new List<string> { "Rice", "Blue fish", "Nori", "Gukan" };
     var nigiriSushi = new NigiriSushi(ingredients, Name);
     return nigiriSushi;
 }