public IActionResult AddPizza(Model.PizzaModel model)
        {
            if (!ModelState.IsValid)
            {
                return(View());
            }

            pizzas.Add(model);
            return(Redirect("/Menu/PizzaList"));
        }
        public IActionResult EditPizza(Model.PizzaModel model)
        {
            if (!ModelState.IsValid)
            {
                return(View());
            }
            var index = pizzas.FindIndex(x => x.Id == model.Id);

            pizzas[index] = model;
            pizzas.Add(model);
            return(View("PizzaList", pizzas));
        }