Fresh or dried, pasta should always be cooked in a large quantity of fiercely boiling salted water. Use about 1 tablespoon salt per 3 quarts water. Estimate 6 quarts water per 1 pound pasta, except for delicate filled pastas and very large noodles such as lasagne, which will need 9 to 12 quarts water. In either case, cooking more than 2 pounds of pasta at once invites problems of uneven cooking and draining. Adequate water and frequent stirring are the two keys to eliminating the problem of pasta sticking together. Adding oil to the water has little effect except to keep the pot from boiling over. Unless the strands are outrageously long and cannot fit into the pot without cracking, do not break pasta before cooking.
Since pasta cooks quickly and is at its best as soon as it is cooked, have everything ready before you startΓÇöthe sauce prepared, a large colander set in the sink for draining, and a serving bowl and dishes warming in the oven. Once the salted water is rapidly boiling, add the pasta all at once. As soon as the pasta softens slightly, give it a stir, partially cover the pot, and let it continue to boil vigorously, stirring often to keep it from sticking together.
Different pastas have different cooking times, and the only test for doneness is to lift a piece from the pot and taste it. Italians consider the ideal state al dente (to the tooth), which means tender but firm—no raw flour taste and enough firmness to give a pleasing resistance to the bite. Start testing fresh pasta and very thin shapes after about 30 seconds, spaghetti and linguine after 4 minutes, and thick macaroni after 8 minutes. Once the pasta tastes done, do not waste a moment—empty the pot immediately into the colander and quickly toss the colander to rid the pasta of as much water as possible. In a few recipes, some of the pasta water is ladled from the pot just before draining and blended into the sauce. Usually these are sauces based on sautés of seasonings, such as garlic and olive oil, or sautés of vegetables. The starch, salt, and liquid extend the sauce and bring seasoning and body to it. Adding more oil would make the sauce too unctuous and heavy. The small amount of starch in the pasta water also encourages these light sauces to cling to the pasta.
Combine the drained pasta with its sauce over heat if possible for maximum flavor, or simply toss the hot pasta and sauce in a warmed serving bowl. Either way, pasta is best eaten hot without delay. Rinse pasta only if it is destined to be baked (for example, in lasagne or stuffed shells) or to be eaten cool in a salad. The starch that clings to unrinsed pasta helps the hot pasta meld with the sauce.
