public static Receipt AddReceipt(Receipt receipt) { var rec = new Receipt(Helpers.GenerateId(ListOfReceipts), receipt.Name, receipt.Description); receipt.Ingredients.ForEach(i => { rec.AddIngredientToReceipt(i); if (!ExistsInIngredientsList(i.Name)) { AddIngredient(i.Name, i.UnitMeasure); } }); ListOfReceipts.Add(rec); return(rec); }