01 -
Cut the peeled potatoes into pieces about 3/4 inch big (roughly 6 cups). Lightly boil them for about 5-6 minutes so they're starting to soften but not completely cooked. Drain all the water off.
02 -
Lightly coat a 9x13-inch baking dish with oil or non-stick spray. Mix the warm, drained potatoes with the ham and 1 cup of cheese in the dish. Toss them together gently and set aside.
03 -
In a big frying pan over medium heat, melt the butter. Stir in the garlic and onions, cooking for 3 minutes or until the onions soften.
04 -
Mix in the flour and seasonings, blending until smooth. Lower the heat and pour the milk in slowly, stirring as you go. Let it cook for 3-5 minutes, stirring often, until it's thick like gravy. Taste it and tweak the seasoning if needed.
05 -
Pour the warm sauce over the potato mixture in the dish, stirring gently to coat everything evenly. Cover the dish with foil and bake at 375°F for 30 minutes. Then, remove the foil, sprinkle the rest of the cheese on top, and bake uncovered for another 5-10 minutes or until bubbly and golden.
06 -
Top with your favorite garnishes, like fresh herbs or a splash of hot sauce, if you'd like. Let it rest for a few minutes before serving.