Bring a large pot of salted water to a boil. Add the broccoli rabe and blanch briefly -- about 3 minutes. Drain and set aside.

In a large skillet, heat olive oil over medium heat. Add pancetta and sauté until crisp, about 4 minutes.

Add the garlic and crushed red pepper and cook for 2 minutes, or until the garlic is fragrant. Do not allow the garlic to brown.

Add the broccoli rabe and chicken stock, partially cover the pan and cook, stirring occasionally, until the greens are tender, 5 to 7 minutes. Season with salt, if necessary.

Serve hot or warm, with some of the cooking liquid ladled over the top.