Preparation
For the corn porridge
Put the chorizo, coriander stalks and half an onion in a pot of water. Boil for 20 minutes. Remove the chorizo and strain. Reserve the broth. Remove the skin from the chorizo and cut into small cubes.
Put olive oil and onions in a saucepan. Sauté for 3 minutes over a low heat.
Then add the chopped garlic and half the broth and reserve the rest.
Put the maize meal and maize flour in a saucepan of cold water. Add the fleur de sel. Cook over a low heat, stirring constantly, taking care until it starts to boil.
The aim is for the texture to be fairly solid. The secret is to start with the broth cold and gradually add more as the mixture thickens until it reaches the desired consistency and is cooked.
Allow to solidify in the refrigerator for 2 hours. Cut into 1cm cubes. Set aside.
For the cataplana
Fillet the mackerel and remove the belly bones and season with fleur de sel, lemon thyme and a little olive oil. Julienne the peppers and slice the onions in half-moons, chop the garlic and cut the tomatoes in halves. Wash the shellfish well.
Put olive oil, the lemon thyme, crushed garlic, bay leaf, lemon grass and chillies in the cataplana. Cook gently over a low heat until the oil is infused with the aromas. Then add the onions and peppers, close the cataplana and cook over a low heat for another 5 minutes.
Open the cataplana, splash with white wine and add the tomatoes, paprika, samphire, razor clams, cockles and rolled mackerel fillets, olive oil and cubes of corn porridge on top with a little fleur de sel.
Close the cataplana again and cook for 8 minutes over a high heat. Adjust the seasoning. Finish with chopped coriander.
Suggestion: serve on a slice of toasted carob bread with olive oil and garlic.