A key ingredient common to all Italian pasta dishes is l’acqua di cottura, the residual water that was used to boil the pasta. Literally translated to mean “the water of cooking” or cooking water which they consider to be liquid gold. The water used to boil your pasta is makes your pasta dish more delicious and helps the sauce adhere to the pasta better while also improving the flavor and texture of the sauce. L’aqua cottura adds moisture and makes the pasta creamy without adding too much oil or grease.
The magic of pasta water is due to the starch the pasta releases as it cooks so its important to use a good quality artisan pasta. Use only as much water as you need to cover the pasta as it boils (typically 1 pound of pasta to 4 quarts of water at a rolling boil). As long as you give the pasta a few vigorous stirs during the first two minutes of cook time the noodles will not stick together. This is essential because it is at this moment when the pasta can clump together as the first layers start to soften and release starch. Time according to package instructions and when the pasta is done the starch content will be concentrated in a ghostly glaze in the pasta water.
Drain but retain a few tablespoons of the water to add to the pasta as you finish it with the sauce in a separate pan. The sauce will adhere to the noodles in a beautiful marriage of the two and you will have a flavorful pasta with a thick, creamy sauce.