Riso, Patate e Cozze alla Pugliese — Layered Rice, Potato and Mussel Bake

Ingredients

• 1 kg fresh live mussels, scrubbed, bearded — cozze Tarantine or best available
• 400 g Arborio rice, raw, unrinsed
• 500 g waxy potato, peeled, sliced thinly
• 2 ripe tomatoes, diced
• 1 white onion, finely chopped
• 1 small bunch flat-leaf parsley, finely chopped
• 80 g Pecorino, finely grated — not Parmigiano
• 80 ml extra-virgin olive oil, plus extra for drizzling
• 1 tsp fine sea salt, or to taste

Method

1. 1
   Scrub and beard the mussels. Place them in a dry wide pan over high heat. Cover and heat only until the shells open — remove each mussel the moment it gapes. Discard any that remain shut. Pull away and discard one half-shell from each mussel; keep the mussel in the remaining half-shell. Strain all accumulated liquor through a fine sieve lined with muslin and reserve. The liquor should smell clean and briny; discard any mussel whose liquor smells off.
2. 2
   Oil the base of the tiella (or a thick baking dish or cast-iron skillet) generously with olive oil. Arrange the potato slices in a single, overlapping layer across the base. Season with salt, a drizzle of olive oil, and a third of the grated Pecorino. The potatoes should cover the base completely without gaps.
3. 3
   Lay the mussels in their half-shells in a single, close layer over the potato, open side up. They should sit snugly, each mussel in its pocket.
4. 4
   In a bowl, combine the raw Arborio rice with the diced tomato, chopped onion, parsley, a third of the Pecorino, a drizzle of olive oil, and the strained mussel liquor. Season with salt. Spread this mixture evenly over the mussels to form the rice layer. If the mussels yielded little liquor, add a small amount of water so the liquid reaches the top of the rice layer. This is the step on which the dish lives or dies: insufficient mussel liquor means the rice will not cook and the briny character of the dish will be lost — every drop of liquor must be reserved and used.
5. 5
   Scatter the remaining Pecorino over the surface. Drizzle generously with olive oil. If the tiella is deep, repeat the potato, mussel, and rice layering sequence before finishing with Pecorino and oil.
6. 6
   Cover the tiella tightly with foil. Bake at 200 °C for 40 to 45 minutes. After this time, lift a corner of the foil and press the surface of the rice with a spoon — it should feel set and have absorbed its liquid, with no visible pooling.
7. 7
   Remove the foil and return the dish to the oven for a further 10 minutes, until the surface has coloured to a deep golden crust and the edges show a faint caramelised border where the olive oil has set against the terracotta. Rest for 5 minutes before serving directly from the tiella.