Bring a large pot or Dutch oven of water to a boil. Add broccoli rabe and cook until tender when pierced with a fork, 3 to 5 minutes. Drain well.
Heat oil in a large skillet over medium heat. Add garlic, anchovies and crushed red pepper (if using); cook, stirring, until the garlic is very light brown, 1 to 2 minutes. Add the broccoli rabe, toss to coat, and cook, stirring occasionally, for 2 minutes more. Season with salt and pepper.
Absolutely delicious! Make sure to salt the water, otherwise the rabe will be a little bitter, however you don't need salt for the saute, the anchovies add enough salt. Don't omit the anchovies, they make the meal delicious.