As soon as you have bought the clams, take them out of the package, wash each of them vigorously under cold running water for at least 5 minutes, and then leave them to soak in a couple of changes of cold water for a further 5 minutes or so. Rinse and dry them well, preferably with a towel that's been run over a hot oven rack.
Get a large pan, one with a lid, that's big enough to hold all the clams without them being too crowded.
Heat 3 tablespoons of olive oil over medium-low heat. Add the garlic and the chile de Arbol and saute for 2 to 3 minutes.
After that, add the razor clams and saute for 2 to 3 more minutes.
Add the white wine and bring it to a boil.
Add the remaining olive oil and the minced parsley, season with a pinch of salt and pepper, turn down the heat to low, cover and allow to simmer for 5 minutes.
Mix well and eat.
Serving Suggestions: This dish is traditionally served with an accompaniment of bread. You can also provide slices of lemon to squeeze on the clams.