Potato and Anchovy Casserole with Tomatoes (Italian Basilicata Patate alla lucana)

Italian cuisine is not generally known for potato gratin dishes. But here's one from the little-known cuisine of Basilicata that is sure to be a crowd pleaser: patate alla lucana, potatoes layered with onions and tomatoes, scented with oregano and pecorino cheese. Considered a side dish or contorno, I sometimes like to "reinforce" the classic recipe with mozzarella and anchovies, turning it into a light main course or one-dish supper. And while the tomatoes mark this as a traditional summer dish, I made patate alla lucana using canned tomatoes on a recent chilly January evening. It was perfectly delicious. The name alla lucana refers to Lucania, the ancient land of the Lucani people which roughly coincided with the current region of Basilicata, but included parts of Campania, Puglia and Calabria as well. Lucano is often used today to refer to modern day Basilicata. The dish is also known as patate arraganate or patate raganate.

1½ lbs potatoes, peeled and sliced (750 g)
1 lb tomatoes, peeled and sliced or canned tomatoes, drained and sliced (500 g)
1 medium onion, thinly sliced
3-4 oz mozzarella or scamorza (100-150 g)
3-4 fillets anchovies
dried oregano
pecorino cheese, freshlygrated
extra-virgin olive oil
sea salt
black pepper, freshly ground
breadcrumbs

Preheat an oven to 350°F (175°C/155°C fan, Gas Mark 3). Grease the bottom of a baking or gratin dish with olive oil.

Lay down a layer of potato slices in the prepared baking dish. (I like to lay them in slightly overlapping rows, like roof tiles, but you needed be so "pignolo" if you don't care about looks.) Sprinkle the potatoes with salt. Then lay down some tomato slices here and there, along with some of their juice, then some onion slices. Add the mozzarella or scamorza and a few anchovies. Sprinkle over some oregano and then grate some pecorino on top. Season with salt and pepper. Drizzle everything with olive oil.

Repeat this layering process until you have run out of potatoes. Top the final layer of potatoes with some tomatoes, generous amounts of grated pecorino and a nice sprinkling of breadcrumbs. Drizzle olive oil all over, in a cross-hatch pattern so the crumbs are well impregnated with oil.

Bake for a good hour or so, or until golden brown on top and the juices that the tomatoes will have given off has (mostly) cooked off. If the top is not done to your liking after an hour, increase the oven temperature to 400°F (204°C/184°C fan, Gas Mark 6) and continue baking for a few minutes more.

Let the potatoes cool off for a good 10-15 minutes before serving.

Makes 4-6 servings as a side course.

Cook's Notes:

• The recipe for patate alla lucana would likely work with any kind of potatoes. But I like to use either "all purpose" or waxy potatoes, the kind you would use for potato salad, rather than the floury sort (like Russets) for mashed potatoes. White onion is often called for, although I've used the usual yellow onions with fine results, and I imagine red onions would also serve well. Garlic is sometimes added along with the onion, and minced parsley along with the oregano. And you could add capers and/or olives as well for even more flavour. As mentioned, you can omit the tomato, in which case I would add a splash of wine or water to moisten the potatoes before baking.
• The scent of oregano is one of the primary characteristics of patate alla lucana. Be liberal but not so liberal that you overwhelm the other flavours. Oregano is an herb typical of southern Italian cooking, but it's not used with quite the abandon as some people imagine, or as you might be led to believe from some Italian-American cooking.
• As with other oven-roasted potatoes recipes, the final rest is an important step that you shouldn't skip. The dish will cool off from the tongue-scorching temperature at which it comes out of the oven, of course. But even more importantly, the rest also allows the pan juices to seep into the potatoes and lend them extraordinary flavour. It makes a world of difference.