Portugal (Alentejo origin)
The lagareiro is the olive oil producer — and this preparation makes the connection explicit. Thick, skin-on salt cod portions are lightly oven-dried to firm the flesh, then submerged in an extraordinary quantity of olive oil with garlic and herbs and baked at high heat until the skin crisps and the flesh confits in the oil. The result is simultaneously roasted and confit — the skin shatters, the flesh is moist from the oil bath, and the entire preparation reeks gloriously of garlic and good Portuguese olive oil. This is the dish that demonstrates Portuguese reverence for both olive oil and bacalhau simultaneously.
The cod must be very thick — the single loin is ideal. Pat dry very well and rest uncovered in the refrigerator for 2-4 hours to dry the surface before cooking. Use a large, deep earthenware or cast iron dish. Cover the cod with olive oil — genuinely cover it, not drizzle over it. Add smashed garlic cloves generously. Cook at 220°C for 20-25 minutes — the surface should be caramelised.
The cooking oil that results is extraordinarily flavoured — use it for pa de casa (crusty bread for dipping), roasting potatoes, or dressing salads. Serve with roasted potatoes cooked in the same olive oil and garlic. Pair with white Alentejano wine. The lagareiro is the Portuguese equivalent of the Spanish confited fish technique.
Using thin pieces — they fall apart and overcook before the skin crisps. Not drying the surface — steam prevents the skin from crisping. Using mediocre olive oil — the dish will taste of the oil. Under-garlicking — the garlic is a primary flavour component.
My Portugal by George Mendes