Set up your Q for indirect cooking with the trivet and convection tray in place. Preheat on high for 10 minutes.
Grease the casserole dish with melted butter.
Line a bowl with sheets of paper towel and pour the corn into the centre. Pick up the paper towel and squeeze to remove the moisture from the corn.
In a large bowl combine the flour, polenta, cheese, sugar, and salt and mix thoroughly. Stir in the corn and chives and blend well. Add the buttermilk, butter, and eggs and stir through. Pour the mixture into the casserole dish and level the surface.
Once the Q is preheated, turn to the roast setting. Place the casserole dish on the trivet. Bake the corn bread until a skewer inserted into the centre comes out clean, 45 to 55 minutes.