Tiella di Riso, Patate e Cozze

Ingredients

Equipment Needed

• •12-inch round terracotta baking dish or 9-by-13-inch enameled baking dish
• •Mandoline or very sharp knife for slicing potatoes
• •Stiff brush for cleaning mussels

Instructions

1. 1

   Clean the mussels

   Place the mussels in cold water and scrub them thoroughly. Pull away the beards, those fibrous threads protruding from the shells. Discard any mussels with cracked shells or any that remain open when tapped sharply. A dead mussel will poison a dish. Live mussels close when disturbed. This is your test.

   Buy mussels the day you cook them. They should smell of the sea, nothing more. Any ammonia odor means they have turned. Walk away.
2. 2

   Prepare the potatoes

   Slice the potatoes as thin as you can manage, about one-eighth inch. A mandoline helps, but a sharp knife and patience work equally well. Place the slices in cold water to prevent browning. Drain and pat dry before layering.

3. 3

   Prepare the baking dish

   Heat the oven to 400 degrees Fahrenheit. Generously oil a 12-inch round or 9-by-13-inch baking dish, preferably terracotta or enameled cast iron. The vessel matters. Thin metal conducts heat too quickly and burns the bottom before the rice cooks through.

4. 4

   Build the first layer

   Arrange half the potato slices in overlapping rows across the bottom of the dish. They should cover the surface completely with slight overlap, like roof tiles. Season with salt and pepper. Scatter half the onion slices and half the garlic over the potatoes. Sprinkle half the raw rice evenly across.

5. 5

   Add the mussels

   Arrange the mussels in a single layer over the rice, hinged side down so they will open upward as they cook. Tuck them close together. Scatter half the tomatoes, half the parsley, and half the cheese over the mussels. Drizzle with half the olive oil.

   The mussels must go in raw. As they bake, they release their liquor into the rice below. This is the genius of the dish. No broth can replicate what the mussels give.
6. 6

   Build the top layer

   Scatter the remaining rice around and between the mussels. Layer the remaining potato slices on top, again overlapping like tiles. This top layer will brown and crisp. Add the remaining onion, garlic, tomatoes, parsley, and cheese. Drizzle with the remaining olive oil.

7. 7

   Add the liquid and bake

   Combine the wine and water. Pour this mixture slowly around the edges of the dish, allowing it to seep down through the layers. Do not pour directly on top or you will wash away the cheese. Cover tightly with aluminum foil. Bake for 45 minutes.

8. 8

   Finish uncovered

   Remove the foil and continue baking until the top potatoes are golden brown and slightly crisp at the edges, 25 to 30 minutes more. The liquid should be absorbed and the rice tender. If the top browns too quickly, tent loosely with foil. The dish is done when a knife slides easily through the layers.

   The rice cooks in the steam and mussel liquor trapped beneath the potato lid. If you open the oven repeatedly, you release this steam and the rice will remain hard. Patience.
9. 9

   Rest and serve

   Let the tiella rest for 10 minutes before serving. This allows the layers to set. Carry the dish to the table and serve directly from the pan, scooping through all the layers to give each person potatoes, rice, and mussels together. Discard any mussels that have not opened.

Chef Tips

• •The potatoes must be sliced thin enough to cook through but thick enough to hold together. Practice with a mandoline if you have one. If your slices vary in thickness, the dish will cook unevenly.
• •Do not substitute canned or frozen mussels. The dish depends on fresh mussels releasing their liquor as they bake. Without this, you are making something else entirely.
• •Pecorino Romano provides the proper salinity. Parmigiano-Reggiano is too sweet for this dish. The cheese should echo the sea, not fight against it.
• •If after baking the rice seems underdone and no liquid remains, add a splash of hot water, cover with foil, and return to the oven for 10 minutes. Ovens vary. Trust your judgment.

Advance Preparation

• •The mussels must be cleaned within a few hours of cooking. Store them in the refrigerator covered with a damp towel, never submerged in water.
• •Potatoes can be sliced and held in cold water for up to 2 hours. Drain and dry thoroughly before layering.
• •The assembled dish does not hold well. This must be baked and served. Leftovers can be reheated the next day in a 350-degree oven, covered, for 20 minutes, but the mussels will toughen.

Frequently Asked Questions

Nutrition Information

1 serving (about 350g)