Bring a large pot of water to boil for the pasta. Salt the boiling water. Add the pasta and cook until al dente, stirring in the broccoli rabe during the last 2 minutes of cooking time. Drain the pasta and the broccoli rabe; set aside 1/2 cup of the cooking water.
In the same pot, heat 1/4 cup olive oil over medium. Add the garlic and crushed red pepper and cook, stirring often, until the garlic softens, about 2 minutes. Stir in the pasta, broccoli rabe, reserved pasta water and half the lemon zest; season generously with salt and pepper. Cook, stirring occasionally, until warmed through, about 2 minutes.
Divide the pasta mixture among plates. Top each serving with 2 tbsp. goat cheese. Drizzle with olive oil and sprinkle with the remaining lemon zest.