01 -
Preheat oven to 190°C. Grease a ceramic or glass baking dish with a portion of the butter.
02 -
In a saucepan over medium heat, combine heavy cream, whole milk, minced garlic, salt, black pepper, and nutmeg. Warm gently, stirring occasionally, until mixture is heated through but not boiling.
03 -
Arrange half of the sliced potatoes in an even layer in the prepared baking dish. Pour half of the warm cream mixture evenly over the potatoes.
04 -
Sprinkle half of the shredded cheddar and grated Parmesan evenly over the potatoes.
05 -
Top with the remaining sliced potatoes, pour over the rest of the cream mixture, and finish with the remaining cheddar and Parmesan cheese.
06 -
Dot the surface with the remaining butter. Cover the dish tightly with aluminum foil.
07 -
Bake in the preheated oven for 40 minutes.
08 -
Remove the foil and continue baking for an additional 20 minutes, or until the surface is golden brown and bubbling.
09 -
Allow the gratin to cool for several minutes before portioning and serving.