Step 1

Trim thick stems from broccoli rabe and reserve for another use (like a stir-fry). Coarsely chop greens and remaining tender stems; set aside.

Step 2

Heat oil in a large Dutch oven or other heavy pot over medium-high. Using your hands, grab small clumps of sausage (you’re going for rustic meatballs about the size of a golf ball) and add to pot. Cook, turning each piece as it becomes crusty, until deeply golden brown all over, about 4 minutes. Using a slotted spoon, transfer sausage to a plate, leaving fat behind. Remove pot from heat and reserve. If sausage has given off a lot of fat, tip some of it into a bowl; you want about 2 Tbsp. left in the pot (save the rest for another use—like frying eggs).

Step 3

Meanwhile, cook pasta in a large pot of generously salted boiling water, stirring occasionally, until just shy of al dente, about 1 minute less than package directions (it’ll finish cooking in the sauce). Drain pasta, reserving 1½ cups pasta cooking liquid.

Step 4

Set reserved pot with fat over medium-low heat. Add garlic and cook, stirring and scraping up any browned bits, until softened slightly, about 2 minutes. Add reserved broccoli rabe, season with salt and pepper, and cook, stirring, until greens are wilted and bright green, about 4 minutes. Return sausage to pot along with any juices on the plate. Break up sausage into smaller but still coarse pieces with a wooden spoon.

Step 5

Add butter, pasta, and ¾ cup pasta cooking liquid to pot. Cook, tossing often and adding more pasta cooking liquid a tablespoon or two at a time if needed, until pasta is coated in sauce, about 3 minutes. Remove from heat, add lemon zest and lemon juice, and toss to coat.

Step 6

Divide pasta among bowls and top with pistachios and Parmesan.