Begin cooking pasta when sauce is done and NOT BEFORE. For best results, your sauce should be done cooking and ready BEFORE you begin cooking your pasta.
Start with a LOT of water. 1 gallon of well-salted water per pound of pasta is a good rule. The water should taste like seawater. (Approximately 2 tablespoons of salt per gallon of water)
Don’t add oil! It does nothing but float to the top and make the pasta greasy as it is drained. Nasty.
How to cook
Don’t add pasta to the pot until the water is at a rolling boil. ROLLING.
Stir the water to get it moving. Add pasta. Immediately stir again. Keep an eye out for clumps of pasta. Stir till pasta separates. Stir again, then continue to stir cooking pasta AT LEAST every two minutes of cook time to keep pasta from sticking to itself.
If you cannot use 4 quarts of water per pound of pasta or you are cooking a lot of pasta at one time, you will need to stir the pasta MUCH MORE FREQUENTLY to keep the pasta from sticking to itself or burning to the bottom of the pan.
When is it done?
Most pasta is done after 8-10 minutes. Size matters and small shapes will be done more quickly than larger pieces.
Check for doneness early and often. Check for doneness by eating a piece. It should be soft with a gentle bite right in the center. This is called al dente and is considered the best way to serve pasta.
Remove pasta when it is SLIGHTLY under your target level of doneness to compensate for carry-over cooking.
How to sauce
Sauce immediately: Cooked pasta can’t sit around - it will stick to itself and become mushy as it continues to cook.
Don’t rinse your pasta (unless you are precooking pasta - in that case you may stop the cooking process by shocking the pasta under cold running water).
Don’t add oil to cooked pasta - that will keep the sauce from sticking.
Deposit pasta directly into sauce, swirl carefully, then plate. Never, EVER, pour sauce over plain pasta. It may look pretty, but the sauce won’t stick and the eating experience will be poor.
Save some of the cooking water! Reserve about ½ cup - it's flavorful, somewhat salty, and starchy. It can be used to loosen a thick sauce without diluting body or flavor.