Cheesy potato and lentil gratin

Turn the oven on to 200 °C, convection if you have it. It'll heat up while the lentils cook.

Put the 120 g of green lentils in the saucepan with 3 times their volume of cold water, no salt. Bring to a boil then let them simmer 25 min, drain and set aside.

Peel the 0.5 kg of potatoes and cut them into rounds about 3 mm thick. Peel the onion and garlic, slice the onion and finely mince the garlic.

While the lentils cook, drop the rounds into a second saucepan of salted boiling water, or into the lentil saucepan once the lentils are drained and rinsed. Cook 8 to 10 min, then drain.

Heat 1 tbsp of olive oil in the skillet over medium heat. Sauté the onion for 7 min, adding the garlic for the last minute.

In the bowl, mix the drained lentils, the onion and garlic, the 8 cl of crème fraîche, the nutmeg, salt and pepper.

Spread half the potatoes in the dish, cover with all of the lentil mix, then finish with the rest of the rounds. Season lightly with salt and pepper.

Spread the 60 g of shredded cheese over the top in an even layer.

Bake 20 min at 200 °C, until the top is nicely golden and a knife tip slides into the potatoes with no resistance. Let it rest 5 min before serving.