Set up your Q for indirect cooking with the trivet and convection tray in place. Preheat on high for 10 minutes.
Brush the casserole dish with the 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.
Combine the flour, polenta, cheese, sugar and salt in a large bowl. Mix thoroughly, stir in the corn and chives until well combined. Finally, 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 for 45-55 minutes, or until a skewer inserted into the centre comes out clean.