It’s always tricky to accurately “measure out” stick, or straight, pastas. For straight pastas, such as spaghetti or fettuccine, you can purchase a little gadget called a spaghetti measure from amazon.com. Ironically, the thinner the pasta, the less accurate the spaghetti measure will be. Thus, for spaghetti or angel hair, I always use half what the measure calls for. For thicker pastas such as linguine or fettuccine, it’s spot on. The rule of thumb is 2oz of dry pasta (or about 1/2 cup of cooked pasta) equals 1 serving. For most pre-packaged pastas, this will equate to about 1/6 of the bag. Another option is to buy an artisanally dried fresh pasta from a specialty food stores, where the pasta is packaged in these neat little half serving bunches. Just grab 2 bunches and you’re good to go. With non-stick (i.e. straight) pasta varieties, you can use a measuring cup. I usually find 1/3 to 1/2 cup is an appropriate portion for one person (depending on the size of the pasta, of course).