Potato gratin with tuna and eggs

Turn the oven on to 180 °C (thermostat 6) right now: it needs 10 to 15 min to heat up. Butter the baking dish with half of the 10 g of butter.

Peel the 480 g of potatoes and cut them into rounds about 3 mm thick. Peel the 2 small onions and slice them thin.

Drop the rounds into a saucepan of salted boiling water and cook them just 3 min, without letting them fall apart. Drain them well in the colander.

Melt the rest of the butter in the skillet over medium heat and sauté the onions for 5 min until soft and golden, without burning them.

In the mixing bowl, mash the drained tuna from the 2 cans with the onions using a fork. Add the crème fraîche, nutmeg, salt and pepper, then mix.

Spread half the potatoes in the dish, cover with the tuna mix, then finish with the rest of the potatoes. Crack the 4 eggs on top, spacing them out, and season lightly with salt and pepper.

Spread the 50 g of shredded cheese over the whole surface of the gratin.

Bake at 180 °C for 15 min, until the egg whites are fully set and the top is golden. Let it rest 2 min before serving.