Once baked, remove the casserole from the oven and let it rest for about 5–10 minutes. This short rest helps it firm up a bit, making it easier to slice into squares. Cut into 6 pieces and serve warm right from the glass pan.
To keep this true to the simple, Amish-style feel, I stick to four core ingredients, but there are plenty of small tweaks you can make while staying close to the spirit of the recipe. For extra flavor without changing the ingredient count much, you can swap mild cheddar for sharp cheddar, Colby Jack, or even a smoked cheese. If you like a little color, sprinkle dried parsley or paprika on top of the cheese before baking. To get slightly crisper edges, bake on the lower-middle rack and let the casserole go toward the longer end of the baking time, watching that the cheese doesn’t over-brown; if it does, loosely tent with foil. For meal prep, you can shred the potatoes the night before and store them submerged in cold water in the fridge, then drain and pat dry in the morning before assembling. Leftovers reheat well in the oven or air fryer—just warm at 350°F until hot and the edges crisp back up. If you’re cooking for a smaller household, bake the casserole in two smaller glass pans, enjoy one right away, and cool and refrigerate the other for an easy grab-and-reheat breakfast over the next few days.