To begin, preheat your oven to 190°C (375°F). In a large skillet over medium heat, add the ground beef and break it apart with a wooden spoon. Cook until browned and no longer pink, about 6 to 8 minutes. Add the chopped onion and garlic, cooking for an additional 2 minutes until softened. Drain excess fat and transfer mixture to a large bowl.

Pour the cream of mushroom soup and milk into the bowl with the beef. Stir in the salt, pepper and sweetcorn. Mix well until fully combined and evenly coated. This forms the creamy, savoury base of your casserole.

Lightly grease a medium sized baking dish (approximately 20x20cm or 8x8in). Spread the beef and soup mixture evenly in the bottom of the dish, smoothing the surface with a spatula. Ensure it is compact and level for even baking.

Sprinkle 1 cup of the grated cheddar cheese over the meat mixture. Spread it evenly so it melts uniformly during baking. Reserve the remaining ½ cup for the topping.

Place the frozen tater tots in a single, snug layer over the cheese. For best texture and appearance, line them up neatly without overlapping. Keeping them flat ensures they crisp up beautifully.

Place the dish in the centre of the preheated oven and bake for 35 minutes. This allows the tater tots to crisp and the filling to bubble. Avoid opening the oven during this time, as it may affect the browning.

After 35 minutes, carefully remove the dish from the oven. Sprinkle the remaining ½ cup of cheddar cheese over the hot tater tots. Return to the oven for another 5 to 7 minutes, or until the cheese is melted and slightly golden.

Remove the casserole from the oven and let it rest for 5 minutes. This allows the layers to settle and makes slicing cleaner. The resting time also ensures safer handling and enhanced flavour cohesion.

Sprinkle chopped parsley or chives over the top for a fresh finish. Serve warm with a simple green salad or pickled vegetables to balance the richness. A dollop of sour cream on the side adds a tangy contrast if desired.