Preheat your panini pan on medium-high heat.
While the pan is warming up, thinly slice the peaches. Spread the goat cheese on two slices of the bread and top with the peach slices. If using fresh basil, give it a rough chop and divide it between the two sandwiches. If using pesto, spread it on the other two slices of bread and place atop the peaches and goat cheese.
Transfer the sandwiches to the panini pan and grill for 3 to 4 minutes on each side, until the cheese has softened and there are nice dark caramel-brown grill marks on the bread.
Remove from the pan and allow to cool before slicing and packing. The sandwiches can be popped into a toaster oven to be revived when needed, or eaten at room temperature.
