Clean the shellfish, submerge it in individual bowls of water for a few hours to remove any sand; once brushed, rinse the mussels. Shell the prawns, remove the black intestine thread and steam them for 3-4 minutes; drain and place them in a bowl. Peel the cloves of garlic and rinse; trim the courgette and chop it into chunks; rinse the tomato and once deseeded chop it coarsely. Clean, rinse and dry the pepper then dice it; wash the parsley, dry it and chop it finely.Drain the sea slugs and place them in a pan with a clove of garlic, add the tomato and a bit of parsley; cook them over a medium heat for 10 minutes. Drain them, extract the pulp with a toothpick and mix them with the prawns. Place the different clams and the mussels in a pan with half a clove of garlic, a spoonful of white wine and a smudge of parsley over a medium heat.Drain the shellfish discard the ones that have not opened, remove the fish from the shells and mix them with the prawns and the sea slugs. Steam the courgette for 2-3 minutes, place it in a bowl, add the diced pepper and mix well.Bring to the boil a pan of water, add some salt and the saffron pistils, toss the pasta in it, drain it al dente, place it in an oven dish, sprinkle with 2 tbsp of oil, mix it well and cool it.Pour a dash of vinegar in a bowl and the leftover oil, add a pinch of salt and pepper, then whisk these ingredients with a fork; add the parsley and dress the courgettes and the pepper with a spoonful of sauce. Then arrange the pasta in a serving dish, add the shellfish and the vegetables, sprinkle with the rest of the sauce, mix delicately and serve cold.