Soak the clams in plenty of cold water to allow them to loose the sand, then drain them. Brush the mussels and rinse them repeatedly under cold running water, drain them and keep them aside. Once deseeded and deribbed, dice the pepper.Place the clams, the mussels and a slightly crushed clove of garlic into a pan, sprinkle with 2 tbsp of oil, cover the pan and let the shells open up over a medium heat. Remove the closed mussels and clams.Remove the pan from the heat, shell the fish and put them into a bowl (keep a few in the shell to garnish the serving dish later); filter the liquid through a canvas cloth and keep it aside. eat the leftover oil, add the pepper and fry until soft; add the shellfish and their cooking water, season with salt and pepper, if necessary and cook for a few minutes.In the meanwhile cook the pasta in boiling salted water. Drain it al dente and sauté with the clam, mussel and pepper sauce. Sprinkle the dressed pasta with chopped parsley and serve warm after having garnished with a few clams.