Use a mandoline to slice baking potatoes as thinly as possible and spread them out on a clean tea towel to dry off.
Melt butter in a saucepan and add garlic, salt, pepper, and thyme. Let it warm on the stove for a few minutes before turning off the heat, allowing the butter to absorb the flavors.
Take an ovenproof dish or similar, and use a brush to coat the dish with the melted butter.
Place the first layer of potato slices at the bottom of the dish and brush the top of the potato layer with the butter. Continue this process with as many layers as the dish or quantity allows.
Now place a piece of parchment paper on top of the potatoes and place, for example, a wooden cutting board on top of the parchment paper, along with any heavy items you have nearby. The point is to weigh down the cutting board, so the potato layers are pressed together as much as possible.
Bake your Pommes Anna for 90 minutes at 150 degrees Celsius (302 degrees Fahrenheit), while weighted down.
Take the dish out of the oven and let it cool on the kitchen counter.
Cut your Pommes Anna into the desired shape and bake them at 225 degrees Celsius (437 degrees Fahrenheit) for about 10 minutes. Ready to serve!