Preheat and Prepare: First, preheat your oven to 180°C (160°C fan). Grease a 2-litre (or 9x13 inch) baking dish with a little butter or cooking spray.

Combine Wet Ingredients: In a large mixing bowl, combine the melted butter, lightly beaten eggs, and soured cream. Whisk them together until smooth and well-incorporated. I find that using a whisk here helps create a lighter final texture.

Add the Corn: Stir in the drained whole kernel corn and the undrained creamed corn. Mix until everything is evenly distributed. This combination is key to the casserole's texture, giving you both whole kernels and a creamy base.

Mix in the Dry Ingredients: Add both boxes of Jiffy Corn Muffin Mix, the salt, and the black pepper to the wet ingredients. Gently fold everything together with a spatula until just combined. Be careful not to overmix; a few lumps are perfectly fine.

Stir in the Cheese: Add about two-thirds of the grated cheddar cheese to the batter and give it a final gentle stir to distribute it throughout the mix.

Pour and Top: Pour the batter into your prepared baking dish and spread it out evenly. Sprinkle the remaining grated cheese over the top.

Bake Until Golden: Place the dish in the preheated oven and bake for 45-55 minutes. The casserole is ready when the centre is set (a skewer inserted should come out with moist crumbs, not wet batter) and the top is golden brown and bubbling at the edges.

Rest and Serve: Let the casserole rest for at least 10 minutes before serving. This allows it to set up properly, making it easier to spoon out. Garnish with fresh chives if you like, and serve warm.