Heat grill to medium.
Combine sugar and cinnamon.
Brush cut side of peaches lightly with melted butter.
Oil grill and place peaches cut side down on grill for 3-4 minutes until grill marks appear.
Brush bottoms with butter and turn peaches over.
Sprinkle cinnamon-sugar mix over peaches, cover grill and cook 3-6 minutes until sugar melts and caramelizes, and it’s easily pierced with a sharp knife.
Serve immediately with ice cream or makes a great side dish with ham or pork chops.