Casting IEnumberable<T> back to original type with lambda expression

Question

If I have the following how to do I cast the result of the lambda expression back to the Customer type from IEnumerable without having to iterate over it.

public class Customer : CustomerModel
    {
        public List<Customer> CustomerList {get;set;}

        public Customer GetCustomerFromListById(long id)
        {
            return CustomerList.Select(c => c).Where(i => i.Id == id);
        }
    }

Answer 1

Use FirstOrDefault().

   return CustomerList.Select(c => c).Where(i => i.Id == id).FirstOrDefault();

Answer 2

Use .Single(), also Select is redundant:

return CustomerList.Single(i => i.Id == id);

As mentioned in the comments that way you get an exception if it doesn't contain the needed key, which should be the expected behavior.