Published February 1, 2005. From Cook's Illustrated.
What’s the best way to cook pasta?
Pasta is one of those things that is easy to cook, but hard to cook just right. For perfect pasta, you must pay attention to everything from the water-to-pasta ratio to the time between draining and saucing.
Pasta needs to cook in a fair amount of water, although not as much as many cookbooks specify. We recommend 2 quarts of water for up to 1/2 pound of pasta, 4 quarts for 1/2 to 1 pound of pasta, and 6 quarts for 1 to 2 pounds. If you are cooking more than 2 pounds of pasta, use two pots. If cooked in too little water, pasta has a tendency to stick together because the starches released by the pasta grow too concentrated and turn the water into a sticky slurry.
After the water comes to a full roiling boil, add salt (a generous 1 1/2 teaspoons per half pound of pasta; most of the salt will go down the drain with the cooking water) and then the pasta. Stir several times to separate the strands and, if necessary, bend long noodles with tongs to submerge them quickly. Use a spoon to push hot water over ends if needed, then cover the pot until the water just returns to a boil (The lid can be removed at this point to prevent the pot from boiling over; cooking with the lid on doesn’t hasten anything.)
Begin tasting after four or five minutes, especially when preparing thin noodles like spaghettini. Keep checking the pasta every minute or so from then on. As soon as the noodles seem almost al dente—they should still have some chewiness, but the center should no longer be hard or gummy—remove the pot from the heat and drain the pasta. Because the pasta continues to cook after it is drained, you need to compensate by draining when it is a little underdone.
Never shake pasta bone dry. Instead, pour it into a colander, allow the cooking water to flow out, and then shake the pasta once or twice to remove excess liquid. The small amount of cooking water that remains on the pasta helps to spread the sauce and is especially useful when tossing pasta with relatively dry oil-based sauces.
For pasta salad, the rules regarding doneness are a bit different and we recommend that you consult the particular recipe for instruction.