Place sauce ingredients in a small sauce pan, and bring to a boil. Allow to boil for 1-2 minutes, and sauce is ready to eat!
Grill peaches
Preheat grill to medium-high.
Place peach, cut side down directly on preheated grill grates. Grill until marks start to appear, about 5-10 minutes. Turn cut peaches over so the cut side is up and any juices can start to collect in the cavity. Continue to grill until peaches are tender, about another 5-10 minutes.
Pour 1-2 tablespoons caramel sauce over each peach. Top peach with about 1-2 teaspoons cointreau. Serve as is, or top with whipped cream or vanilla ice cream.
Notes
Sauce recipe will make more than you need for the peaches. Serve the leftovers on all kinds of desserts.