Clean the potatoes, peel and cut into slices about 1/4 inch thick.
In a small bowl, combine the margarine, honey and cinnamon and stir until smooth.
Coat the grill with cooking spray and preheat for 5 minutes.
Place the potato slices in the grill and cook for 3 minutes.
Spoon the honey butter over the potatoes and grill for an additional 4-6 minutes.
As the butter melts, it will run into the drip tray.
Place the grilled potatoes on a serving platter and drizzle with the melted honey butter.