Mix together the cornmeal with tablespoon sugar and salt. In a heavy bottom pot, bring coconut milk and water to a slow boil. Now slowly pour the cornmeal mixture into pot while continually whisking. Once all the cornmeal is whisked in, turn heat to low and let mixture cook for another 20 to 30 minutes, mixing very often, until mixture is super thick.
Remove from heat and pour into a well-greased 9x9 pan. Smooth out and place into the fridge to let the polenta set up. This should take about an hour, but can be made a day ahead.
Once you are ready for grilling, ready your grill. Grab polenta from fridge and cut into 6 to 9 squares. (You could also use a biscuit cutter for rounds.) Grab peaches and gently cut each one in half. Lightly brush each side of the polenta cakes with oil and sprinkle with sugar. Sprinkle the peach half with sugar as well. Place peaches and polenta on hot grill and cook each side for about 4 minutes, or until the grill marks appear. Depending on your peaches, they might need a few extra minutes to cook until soft. If so, just turn heat down a bit to avoid burning them.
To serve, take a piece of grilled polenta and top with a grilled peach (1 half or 2). Top with whipped coconut or regular cream. Serve.