‘It’s as easy as a sandwich.’ Martin Morales is setting out the ingredients for seabass ceviche, one of the most popular dishes at his thrumming Soho restaurant, itself called Ceviche. Because of encounters with sushi making kits, we’d made the assumption: ‘Raw fish, painstaking, don’t bother.’ But it turns out that Peru’s national dish, which is best made completely fresh, is one of the easiest things ever. Apparently.

‘The key ingredient is a really fresh piece of fish,’ says Martin. ‘Or you could substitute grey mullet, seabream, sole… halibut is gorgeous. Then you simply need fine sea salt, lime juice and chilli.’ This recipe also uses red onion and sweet potato, plus ginger and garlic for the tiger’s milk, which is the wonderful marinading juice that ceviche fans are so mad about.

Martin Morales’ seabass ceviche

You’ll need (to serve four)

  • 600g seabass or other white fish (filleted weight)
  • 2 large red onions, very thinly sliced
  • A few coriander leaves
  • 1 Limo chilli, deseeded and finely diced
  • 1 large sweet potato, cooked and cut into 1cm x 1cm cubes

For the Amarillo Tiger’s milk

  • Juice of 5 limes
  • ½ tsp finely chopped root ginger
  • ½ tsp finely chopped garlic
  • ½ tsp Amarillo chilli paste
  • ½ tsp salt

A sneaky tip from the expert

For optimum freshness, buy your seabass whole and fillet it yourself. Refrigerate it until you come to use it.

  • 1

    Wash the sliced red onion, then let it soak in iced water for five minutes. Drain, blot on kitchen paper, then refrigerate.

  • 2

    Now to make the tiger’s milk. Rrrrr! Roll each lime to ‘loosen’ the juice, then squeeze firmly but gently. Try to avoid tearing the pith, which can embitter your ceviche.

  • 3

    Add the garlic, ginger, chilli paste and salt, then blend until smooth. Try to get hold of real Peruvian chilli such as Amarillo, Rocoto or Limo.

  • 4

    Now take the fish fillets from the fridge and cut into pieces as uniformly as you can. Martin does 2cm by 3cm – some chefs go smaller.

  • 5

    Place in a large bowl, and pour the tiger’s milk on top, combining gently with a metal spoon. Allow the fish to ‘cook’ in the marinade for two minutes. That magic moment when the raw fish is just absorbing the lime and salt.

  • 6

    After two minutes, add the onions, coriander leaves, chilli and sweet potato. Stir gently.

  • 7

    Serve in a small glass dish. Pour any remaining tiger’s milk on top, or serve it in shot glasses.

Ceviche, 17 Frith Street, London W1D 4RG (020 7292 2040; cevicheuk.com)