Preheat the oven to 450F/220C
Slice your washed and unpeeled potatoes thinly with a mandoline slicer or with a sharp knife and put them in a bowl filled with cold water, set aside.
Pour cream in a small saucepan and add fresh rosemary, a bay leaf, salt and a peeled garlic clove cut lengthwise. Slowly bring it to a boil to allow the cream to get infused with herbs and garlic. It should take about 7-10 minutes on low heat.
Butter a 9" round pan and arrange well-drained potatoes slices in layers. Then pour hot cream over the potatoes while reserving 1/4 cup of the cream.
Cover with foil and cook in the preheated oven for 45 minutes.
Take the foil off and test for doneness with a knife, which should pierce them easily.
Change the oven setting to broil/grill. Pour the rest of the cream over the potatoes and sprinkle with grated cheese.
Broil/Grill for 2 more minutes until the cheese is bubbly and slightly browned on top.