2poundsstarchy/floury potatoes(such as Russet, Sebago, Maris Piper, or Désirée)
1teaspoonkosher (coarse) salt
Chopped parsley or dill(optional)
Peel the potatoes and cut them into ⅛-inch-thick slices. Place them in a pot with the milk, cream, nutmeg, mustard, and salt and simmer for 10 minutes.
Meanwhile, preheat the oven to 400°F / 200°C. Cut the clove of garlic in half and rub the cut sides around the inside of a 3 quart baking dish, then smear the butter around the inside of the dish.
Pour the potato and cream mixture into the dish and spread the potatoes out evenly. Bake for 35 to 40 minutes or until golden and bubbling. Serve hot, topped with a sprinkling of chopped parsley, if desired.
Although you may use a mandoline to evenly slice these potatoes, if you have good knife skills a sharp knife will get the job done.
If you choose to add cheese, top with about ⅔ cup grated Gruyere cheese right before baking.
This recipe uses kosher salt (aka cooking salt, kitchen salt, coarse salt outside of the US). If you are using table salt, definitely scale down the salt as that is a saltier type of salt! The type of salt will make a big difference in how salty your food tastes, so keep that in mind.