Where can you order pizza where slices have separate toppings? Anyway...
Using Linq:
// Was "Me.Eat()" supposed to be "this.Eat()"?
Pizza
.Where(slice => slice.Flavor == "Sausage")
.Foreach(sausageSlice => { Me.Eat(sausageSlice); });
The first two lines create a new list with only sausage slices. The third will take that new subset and pass each slice to Me.Eat(). The { and ;} may be superfluous. This is not the most efficient method because it first makes a copy (as do many other approaches that have been given), but it is certainly clean and readable.
BTW, This is only for posterity as the best answer was already given - iterate backward by index.
