Preheat the oven to 204 degrees celsius.Take a square baking dish and grease it thoroughly with butter.
Wash and peel the potatoes, then cut them into slices that are 1/8 inch thick. Put the potatoes into a large bowl of cold water and drain.
Take a pan, pour in the milk, heavy cream, and garlic together. Let it simmer and cook.
Next, put in the potatoes, pepper, salt, and let it simmer and cook for 20 minutes. Keep stirring in between this time.
After this time period, transfer half of the potatoes mixture into the baking dish and sprinkle half of the cheese on top.
Then, pour in the remaining potatoes mixture on top and and pour cream mixture over to cover. Sprinkle the remaining cheese on top of this.
Bake for 40-45 minutes until it is bubbly and has a beautiful golden brown colour on top.
Once cooked, remove from oven and let it cool down. Sprinkle the grated nutmeg on top before serving.