Peel the garlic clove then chop it. Grate the zest of the lemons, squeeze them. Combine the juice, zest, minced garlic and pomegranate balsamic vinegar in a bowl. Leave to macerate for 10 minutes.
Peel the onion and finely chop it. Add it to the lemon/pomegranate juice, salt and pepper, sprinkle with chilli.
Cut the cod fillets into cubes, taking care not to alter their flesh. Place these cubes in the lemon/pomegranate mixture, add extra virgin oil to the squeezed lime. Leave to marinate for at least 30 minutes.
Serve the ceviche with chopped coriander and pomegranate seeds.