For some reason, I've never made clam sauce before, though I love it. This is the red (tomato) kind; maybe sometime in the winter I'll make a white clam sauce. This recipe is also from Marcella Hazan's "Essentials of Italian Cooking," and it couldn't be easier.
The recipe calls for starting with clams in the shell, in which case you scrub them, steam them until the shells open, take out the meat and chop it into small pieces. When I went to Marche Kim Phat last week, I saw they had frozen bags of shelled clams, so that's what I used and they worked fine. However, you don't get the fragrant clam juice that way, so you need to use some bottled clam juice or a cube of fish bouillon in the sauce. I added a little white wine, too.
3T extra virgin olive oil
1 1/2 t finely chopped garlic
2T chopped parsley
2 C canned Italian tomatoes or 6 fresh ripe ones, chopped with their juice (peeling is optional, in my opinion)
a couple of anchovy fillets, finely chopped
hot chili flakes
1 lb. pasta
Heat the olive oil on medium heat in a saucepan, add the garlic, saute until golden. Add the parsley, coating it with oil, then add the tomatoes and their juice, anchovy fillet, and your clam juice or fish bouillon. (Use your judgement - add a little water or wine if it looks like you need it, but remember the tomatoes will render a good amount of juice as they cook.) Stir, turn down the heat to low, cover and simmer for 25 minutes. (At this point, adjust the "wetness" again - if you need to thicken it, either boil the sauce down a bit or add a couple tablespoons of good-quality tomato paste.) You can prepare the sauce to this point ahead of time and reheat it.
Meanwhile, cook your pasta according to package directions so that it will be done when the sauce has finished cooking. Serve with a green salad and a hot crusty loaf of French bread or an Italian ciabatta.
Add salt to the sauce if needed, and some chili flakes to taste. Now add the cut-up, cooked clams, remove from heat, and toss with your cooked pasta, adding a little olive oil on top.