Cod Leek Potato Gratin

In 'williams-sonoma one pot of the day'

Preheat the oven to 375.

Butter a 13-inch oval gratin pan or 4 deep , individual-sized baking dishes.

Cut the potatoes crosswise into thin , uniform slices.

Cut the leeks crosswise into slices about twice as thick as the potatoes.

Season the fish lightly with salt and pepper.

Arrange half of the potato slices in the prepared dish , overlapping them to cover the bottom.

Season lightly with salt and pepper.

Scatter half of the leeks over the potatoes , then arrange the fish slices over the leeks in a single layer , overlapping the slices as necessary.

Top with the remaining leeks , then with the remaining potatoes.

Season with salt and pepper.

Pour the cream evenly over the layers.

Bake for 40 minutes.

Remove from the oven and spoon some of the cooking liquid over the top of the gratin to moisten the potatoes and help them brown.

Continue to bake until the top layer of potatoes is tender when pierced with a sharp knife , about 20 minutes.

Let stand for 10-15 minutes and s.

butter, white potatoes, leeks, cod fish fillets, salt, white pepper, heavy cream