Trucha a la Plancha

Lake Titicaca trout seared on a hot plate with garlic and lime, served with chuño, hominy and a spoonful of raw llajwa

Origin: Copacabana & Lake Titicaca

From the journey of Potato.

Trout is not native to Lake Titicaca. Rainbow trout were introduced from North America in the 1930s and 1940s to develop a fishery at 3,800 metres, and they did so spectacularly, at considerable cost to the lake's endemic Orestias killifish. The result is that the fish most associated with the highest navigable lake on earth arrived less than a century ago, and Bolivians and Peruvians alike now regard grilled Titicaca trout as the dish of the lakeshore. What makes the plate Andean is not the fish but everything beside it. Chuño is the freeze-dried potato of the altiplano, made by leaving tubers out through the frost at night and treading and drying them in the sun by day, repeatedly, over several weeks. The technique is at least a thousand years old, it produces a starch that keeps for years, and it was the storage system that let Andean states hold food against famine. Mote, the large boiled hominy, sits beside it, and llajwa, a raw salsa of locoto chilli and tomato ground on a flat stone, goes over everything. Copacabana, the pilgrimage town on the Bolivian shore, is where most visitors eat it: a row of stalls along the water grilling trout to order on flat steel plates. The cooking is deliberately plain, garlic and lime and a hot surface, because a fish this fresh does not want handling and because the altitude means everything else on the plate has been reconstituted from something dried. The chuño is the part outsiders find hardest and Bolivians find indispensable. It is spongy, slightly smoky, and tastes chiefly of what it is served with, which is exactly the point: it is there to carry the lime, the fat, and the llajwa.

Ingredients

Fish

  • 4 whole trout, about 350g each, cleaned
  • 6 garlic cloves, crushed
  • 3 limes, juiced
  • 2 tsp salt
  • 1 tsp ground cumin
  • 1 tsp coarsely ground black pepper

To cook

  • 3 tbsp oil

To serve

  • 250 g chuño, or 600g waxy potatoes
  • 200 g dried white hominy (mote), soaked overnight
  • 1 lime, in wedges

Llajwa

  • 2 locoto or red chillies, deseeded
  • 2 tomatoes, quartered
  • 1 small handful quilquiña or coriander leaves
  • 0.5 tsp salt

Method

  1. Soak the chuño in cold water for at least four hours, changing the water three times, then squeeze each piece dry between your palms.
  2. The repeated changes of water are what take out the bitterness; chuño soaked once tastes acrid and is the usual reason people decide they dislike it.
  3. Boil the squeezed chuño in salted water for thirty minutes until spongy and tender, and keep it warm.
  4. Boil the soaked hominy in unsalted water for an hour and a half until the grains split, salting at the end.
  5. Make the llajwa: grind the chillies, tomatoes, herb, and salt to a coarse, wet salsa on a flat stone or in a mortar. It should be rough, not smooth, and it is made fresh rather than kept.
  6. Rub the trout inside and out with the garlic, half the lime juice, salt, cumin, and pepper, and leave for fifteen minutes.
  7. Fifteen minutes is the limit. Lime juice will begin to cook the flesh and a trout left in it for an hour goes chalky before it reaches the pan.
  8. Get a flat griddle or heavy frying pan very hot and film it with the oil.
  9. Pat the fish dry and lay them down, and do not move them for four minutes; the skin needs to set and release on its own.
  10. Turn once and give them three or four minutes on the second side, until the flesh at the thickest point parts from the bone.
  11. Squeeze the remaining lime over them off the heat.
  12. Serve each trout with a mound of chuño, a spoonful of hominy, the llajwa, and a lime wedge.

Notes

Change the chuño's soaking water at least three times and squeeze each piece dry; this is the difference between chuño people like and chuño people do not. Do not marinate the fish in lime for more than fifteen minutes. A dry fish and a properly hot plate are what give crisp skin, and moving the fish before the skin releases is what tears it. Llajwa is made fresh for each meal and is not the same thing as a bottled hot sauce; locoto (rocoto) is the correct chilli and a red jalapeño is the nearest common substitute. Waxy potatoes stand in for chuño but the plate loses its altiplano character.

The Gastrographer

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