Preheat a grill to low heat.
In a bowl, combine the cornmeal, baking powder, baking soda, sugar and salt and mix well. In a separate bowl, combine the buttermilk, egg and butter and stir to combine. Add the wet ingredients to the dry ingredients and stir until just combined. Use the vegetable oil to coat the insides of 4 (5-inch) square mini cast-iron skillets. Spoon 3/4 cup of the batter into each of the skillets. Set the skillets on the grill and close the lid. Grill until the cornbread is firm and a toothpick inserted into it comes out clean, 12 to 13 minutes.
Remove the cornbread from the grill and baste with the Honey-Butter mixture. Let the cornbread sit for 5 minutes before removing it from the skillets and serving.
Serve each piece of cornbread with 2 grilled peach halves and a drizzle of honey.
In a medium bowl, combine the butter and honey and whisk thoroughly until well blended. Set aside until the cornbread is cooked. Divide the spread evenly between the 4 cornbreads.