If you were expecting something very complicated, don’t worry. The key to preparing broccoli rabe without a bitter taste is to boil a large pot of water, and add a pinch of both salt and sugar to the water. That’s it! The salt will raise the boiling point of the water so it cooks the broccoli rabe more quickly, while the sugar will cancel out any bitterness. Be careful not to overcook it, either — it only takes about a minute or two to cook.
If you’re using it in another dish (such as my Mostaccioli with Chicken Apple Sausage, Broccoli Rabe, and Bell Pepper), I find it helpful to drain the broccoli rabe in the basket of a salad spinner, then dunk it in ice water or pour cold, running water over it. You can then easily drain all the water out of it by running it through the salad spinner a couple of times.
This general method of using both salt and sugar also works for blanching and/or cooking all kinds of similar leafy green vegetables, including broccoli and swiss chard. So go forth and cook (and eat) your vegetables!
Image credit: http://herbsspices.about.com/od/salads/r/GarlicRapini.htm