Going Through A Foreach When It Can Get Modified? [duplicate]

Answer 1

Perhaps change your Me.Eat() signature to take an IEnumerable

Me.Eat(Pizza.Where(s=>s.Flavor=="Sausage").ToList());

This lets you perform the task in 1 line of code.

Then your Eat() could be like:

public void Eat(IEnumerable remove)
{
    foreach (Slice r in remove)
    {
        Pizza.Remove(r);
    }
}