How to Make It
Preheat the oven to 375°. In a food processor, pulse the bread with the parsley, olive oil, zest and garlic until coarse crumbs form. Season with salt and pepper, then spread on a large rimmed baking sheet. Bake for 7 to 10 minutes, until golden and crisp; let cool.
Light a grill. In a large bowl, toss the broccoli rabe with 2 tablespoons of the olive oil and season with salt and pepper. Grill over high heat, turning occasionally, until crisp tender and lightly charred all over, 3 to 5 minutes. Transfer to a work surface and let cool slightly, then finely chop.
Meanwhile, in a large saucepan of salted boiling water, cook the pasta until al dente. Reserve 1/2 cup of the cooking water, then drain the pasta.
Wipe out the saucepan and heat 1/4 cup of the olive oil in it until shimmering. Add the garlic and crushed red pepper and cook over moderately high heat, stirring, until fragrant and just starting to brown, about 1 minute. Add the pasta, broccoli rabe, reserved cooking water, lemon juice and the remaining 2 tablespoons of olive oil and cook, tossing, until the pasta is coated, about 2 minutes. Season with salt and pepper.
Transfer the pasta to a serving bowl and scatter some bread crumbs on top. Serve right away, passing additional bread crumbs at the table.