Step 1

Bring a large pot of salted water to a boil.

Step 2

Meanwhile, heat a small skillet over medium heat. Add 1 tablespoon of the butter and let it melt. Add the chopped pistachios. Toast for a minute or so until fragrant. Turn off the heat and set aside.

Step 3

Heat a large Dutch oven (or heavy-bottomed pot) over medium heat. Add enough olive oil to coat the bottom. When the oil is hot, add the sausage. Use a wooden spoon to break it into smaller pieces as it begins to brown. Cook for 5-6 minutes until browned and cooked through, stirring often.

Step 4

Transfer the sausage to a plate. Add the red onion, fennel, and a pinch of salt to the pot. Cook for 10 minutes or so until caramelized and tender. Meanwhile, drop the paccheri in the water and cook for 2 minutes less than the package’s instructions, stirring often.

Step 5

Stir the garlic and crushed red pepper into the vegetables. Cook for another 30 seconds. Pour in the white wine. Retrieve a ½ cup of starchy pasta water from the pasta pot and add it in with the wine. Let the liquid come to a boil, reduce the heat, and simmer for 3-4 minutes until slightly thickened. When the pasta is done cooking, drain it and add it to the pot. Stir well to coat and continue to cook for a minute or so.

Step 6

Stir in the spinach, sausage, and remaining 2 tablespoons of butter. Let heat through. Gradually stir in the pecorino cheese until it melts into the sauce. Lastly, fold in the basil and parsley.

Step 7

Taste the pasta and season with more salt if needed. Pour the pasta and all of the sauce into a large serving bowl. Garnish with the pistachios, more pecorino cheese, and any extra fresh herbs.