Preheat and Prepare: First, preheat your oven to 180°C (160°C fan). Grease a 2.5-litre (or 9x13 inch) baking dish with a little butter.

Combine Wet Ingredients: In a large mixing bowl, add the drained whole kernel corn, the cream-style corn, sour cream, whole milk, melted butter, and the beaten eggs. Whisk everything together until it's well combined.

Mix in Dry Ingredients: To the same bowl, add the fine cornmeal, caster sugar, baking powder, salt, pepper, and onion powder. Gently fold these in with a spatula until just combined. Be careful not to over-mix; a few small lumps are perfectly fine.

Add the Cheese: Reserve about a third of the grated cheddar for the topping. Fold the remaining two-thirds of the cheese into the batter. This ensures you get lovely pockets of melted cheese throughout the casserole.

Assemble the Casserole: Pour the batter into your prepared baking dish and use the spatula to spread it into an even layer. Sprinkle the reserved cheddar cheese evenly over the top.

Bake Until Set: Place the dish in the preheated oven and bake for 45-55 minutes. What works best for me is to start checking around the 40-minute mark. The casserole is ready when the edges are golden brown and set, and the centre has a slight wobble to it. It will continue to set as it cools.

Rest Before Serving: Remove the casserole from the oven and let it rest on a wire rack for at least 10-15 minutes before serving. This step is crucial as it allows the pudding to set properly, making it easier to spoon out.