Bring a large pot of salted water to a boil. Add the broccoli rabe and cook until crisp-tender, 2 minutes. Using a slotted spoon, transfer the broccoli rabe to a large bowl of ice water. Once cooled, drain broccoli rabe and set aside. Add the fettuccine to the same pot of boiling water and cook until just tender, about 2 minutes. Drain, reserving 1/2 cup of cooking liquid.
Meanwhile, bring the broth and lemon juice to a boil in a heavy large skillet over medium-high heat. Boil until the broth reduces by half, about 5 minutes. Add the chicken and simmer just until heated through, about 2 minutes. Add broccoli rabe to the chicken broth and stir to combine. Add the pasta, 1/2 cup of Parmesan, pine nuts, parsley, oil, and lemon zest. Toss to coat, adding some of the reserved cooking liquid, 1/4 cup at a time, to moisten. Season the pasta with salt and pepper, to taste. Mound the pasta into bowls and serve. Sprinkle with the remaining Parmesan and serve.