Causa Limeña

Method

Boil peeled yellow potatoes in salted water until a knife slides through with no resistance — roughly 15–20 minutes depending on size. Drain well, then mash while still hot. This matters: hot potatoes absorb the lime juice and oil more readily, creating a cohesive emulsion rather than a grainy paste. Deseed the ají amarillo peppers and blitz them to a fine purée. Fold the purée into the mash along with the lime juice, olive oil, and salt. The acid begins to break down the starch, tightening the crumb and sharpening the flavour. You want something that holds shape but still yields to the spoon — neither soup nor dough.

For the fish layer, poach the white fillet gently in salted water until opaque throughout, then flake it into thumb-sized pieces. This keeps the texture intact; aggressive handling turns it to paste. Toss the flaked fish with finely diced red onion, coriander, lime juice, and black pepper. The raw onion's harshness softens over the next few hours as the acid andean-cuisine pickle-cures it slightly, so season conservatively now. Taste as you go — the fish needs only enough salt to make itself louder.

Line a terrine or loaf tin with cling film for clean unmoulding. Spread half the potato mixture across the base and press firmly to compact it. Layer the fish mixture evenly on top, then seal with the remaining potato. Press down once more so the layers bond slightly. Wrap and chill for at least 2 hours — this firms the dish and lets the flavours marry. The cold also firms the starch, making slicing cleaner.

Unmould onto a cold board and slice into 1.5 cm wedges with a hot, wet knife. Wipe between cuts. Serve at cellar temperature (12–14°C), not straight from the fridge — the potatoes will taste mealy if too cold. A simple avocado salad or boiled potatoes dressed with lime and coriander work as sides. The andean-cuisine principle here is layering distinct flavours vertically, each one coherent, so the eater meets potato, then fish, then potato again with each bite.