How to Make It
Preheat the oven to 350°. Spread the pistachios in a pie plate and toast for about 10 minutes, until fragrant and golden. Let cool to room temperature.
Meanwhile, bring a large saucepan of salted water to a boil. Add the broccoli rabe and cook until crisp-tender, 2 minutes. Rinse under cold water. Squeeze dry, then transfer to a cutting board and coarsely chop.
In a food processor, pulse the pistachios with the garlic until coarsely chopped. Add the parsley and broccoli rabe and pulse until finely chopped. Add the olive oil and process until incorporated. Stir in the Pecorino, season with salt and pepper and serve.