Wash and purge the clams or cockles well: leave in a bucket of cold water with a handful of fine oatmeal stirred in for an hour or so.
Cook the shellfish in a saucepan without any water, stirring from time to time. When all the shells are open, strain and reserve the liquor. Remove the flesh from the shells. Fry the onion and garlic in the extra-virgin olive oil until soft but not coloured, add the parsley and quickly fry. Add the tomatoes and fry for a few minutes, add the white wine, then add the liquor from the shellfish. Season with salt and pepper and a generous pinch of chilli flakes, and reduce well. Add the clams or cockles, bring the sauce to the boil and remove the pan from the heat.
Serve as a sauce for spaghetti. Do not be tempted to serve Parmesan cheese.
If your tomatoes are not very ripe, stir-fry a half cupful of tomato purée in olive oil for a few minutes, and add this to the sauce.
© 1993 Ann and Franco Taruschio. All rights reserved.