A delightful casserole combining crispy potatoes, savory ham, and creamy cheese sauce.
Preheat your oven to 425°F and arrange the oven rack in the center.
Preheating ensures even cooking and a crispy texture.
Spread the frozen potato nuggets evenly in a 9x13-inch casserole dish and bake for 15 minutes.
Ensure the nuggets are in a single layer for even crisping.
Remove the dish from the oven, turn the nuggets using tongs, and bake for another 15 minutes until golden and crisp.
Turning the nuggets helps achieve an even crisp on all sides.
Reduce the oven temperature to 375°F.
Lowering the temperature prevents over-browning during the final bake.
In a saucepan, melt the butter over medium heat.
Use medium heat to avoid burning the butter.
Add the diced onion, salt, and pepper to the butter and cook until the onion is soft, about 4 minutes.
Stir occasionally to prevent sticking.
Stir in the diced ham and cook for 2 minutes.
Ensure the ham is evenly distributed in the mixture.
Sprinkle the flour over the mixture and stir constantly for 2 minutes.
This step creates a roux, which thickens the sauce.
Gradually pour in the milk while stirring, and bring the mixture to a boil. Reduce heat and simmer for 2 minutes until thickened.
Stir continuously to avoid lumps.
Remove the saucepan from heat and stir in 2 cups of the shredded cheese until melted.
Adding the cheese off-heat prevents it from becoming grainy.
Pour the cheese sauce over the baked potato nuggets in the casserole dish.
Spread the sauce evenly for consistent flavor.
Sprinkle the remaining 1 cup of cheese over the top.
For a golden crust, use a mix of cheeses.
Bake the casserole at 375°F for 35 minutes until bubbly and golden brown.
Check halfway through to ensure even browning.
Let the casserole rest for 5 minutes before serving.
Resting allows the flavors to meld and the casserole to set.