Tiella di Riso Patate e Cozze

Ingredients

• 1 kg live mussels, scrubbed and debearded, opened raw into the dish
• 400 g short-grain rice, uncooked, unrinsed
• 600 g waxy potatoes, peeled and sliced 3 mm thin
• 300 g ripe tomatoes, thinly sliced
• 1 medium white onion, finely sliced
• 3 cloves garlic, finely sliced
• 80 g Pecorino, finely grated
• 100 ml dry white wine
• 80 ml extra-virgin olive oil, plus extra for the dish

Method

1. 1
   Heat the oven to 200 °C. Oil a terra cotta tiella or heavy earthenware baking dish thoroughly. Scatter the sliced onion and garlic across the base. Lay the potato slices in a single, overlapping layer — 3 mm is the maximum; thicker slices will not cook through in the time the rice requires. The potatoes are done at this stage when they form an unbroken, oil-glistening floor across the dish.
2. 2
   Open the raw mussels over a bowl, catching every drop of their liquor. Reserve the liquor. Discard any mussel that will not open under firm pressure. Distribute half the sliced tomatoes over the potato layer, then scatter the uncooked rice evenly across the tomatoes in a level layer. Drizzle half the olive oil over the rice. This is where the dish lives or dies: the rice must lie flat and even, with no gaps or mounds, so that it absorbs the rising mussel liquor uniformly during baking — uneven rice means uneven cooking, and no stirring will correct it.
3. 3
   Arrange the opened mussels, shell side down, across the rice layer in a single tier. Lay the remaining tomato slices over the mussels. Pour the reserved mussel liquor and the white wine evenly over the surface. Drizzle the remaining olive oil across the top. Scatter the grated Pecorino over everything in an even layer. The surface should appear thoroughly moistened but not pooled with excess liquid — the mussel liquor and tomato moisture are the only cooking medium; no broth is added.
4. 4
   Cover the dish tightly with foil or a lid and bake at 200 °C. After 30 minutes, remove the cover. The rice should have begun to swell and the liquid should be visibly reduced. Continue baking uncovered for a further 15–20 minutes. The dish is ready when the potato yields without resistance to a skewer inserted through all layers, the rice is fully swollen and has absorbed the surrounding liquid, and the Pecorino across the top is deep golden and faintly crisped at the edges.
5. 5
   Remove the tiella from the oven and allow it to rest, uncovered, for at least 10 minutes before carrying it to the table. The surface crust should hold its colour and not steam back to pallor during resting. Serve directly from the vessel.