Preheat the oven to 425F/220C and have ready a shallow earthenware or glass baking dish, about 2 quarts/2 litres in capacity.
In a medium saucepan, combine the potatoes, milk, garlic, salt, and a good grating of nutmeg. Bring to a simmer over medium-low heat and cook, stirring the potatoes and scraping the bottom of the pan regularly to prevent sticking, for 5 minutes. The milk will thicken to a cream consistency; if you find the potatoes are absorbing most of the milk as they cook, add a little more to the pan. You should aim to have about ½ cup/120ml liquid in the pan after the potatoes have simmered for 5 minutes.
Scrub the potatoes, but don't peel them. With a sharp knife of mandolin slicer, cut the potatoes into ⅛-inch/3mm slices. Do not rinse after slicing.
My favourite food in the whole wide world is toasted buttered bread and sometimes I eat it for every meal of the day. My second favourite food is cheese. I'm left handed and have to use two spatulas to flip pancakes...