How to make
Boil the potatoes. Allow them to cool before you start cooking, peel them and grate them on a coarse grater into a bowl.
Add all the other ingredients to them and mix well with grated cheese at the end. You can pour in an extra 3 1/3 tbsp (50 ml) of oil.
Spread the mixture into a greased oven dish. Put the potato gratin to bake in a moderate oven preheated to 390°F (200 °C) until ready.
Optionally sprinkle the finished gratin with a little grated cheese and return to the oven for it to melt.