This creamy spinach pasta sauce is a wonderful way to get your greens. It's loaded with basil, parsley, and a few other simple ingredients. The trick? Blanching the spinach before cooking makes for the greenest basil spinach sauce ever.
Bring a large pot of water to a boil. Once boiling, add the spinach and boil it for 30 seconds. Transfer to an ice bath and set aside.
Sauté the onions and garlic:
Heat 1 tablespoon olive oil in a small pot over medium-low heat. Add the onion and cook, stirring occasionally, for 10–12 minutes until very soft.
Add the roughly chopped garlic and cook for 1 minute. Season with a pinch of salt and turn off the heat. Set aside.
Cook the pasta:
To the pot of boiling, salted water, add the pasta and cook until al dente. Scoop out 1 cup of the pasta cooking water and set aside.
Prepare the sauce:
Drain the spinach and squeeze out as much of the excess water as possible.
Place the basil, parsley, pistachios, spinach, and lemon juice in a food processor or blender. Pulse until finely minced. Add 2 tablespoons extra virgin olive oil and pulse again until incorporated.
Add the mascarpone, cooked onions and garlic, and ½ cup of Parmigiano-Reggiano to the food processor along with a big pinch of salt. Pulse until smooth. Add half of the pasta water and continue blending until smooth. Transfer the sauce to a bowl.
Sauce the pasta:
Add the cooked pasta to the bowl of sauce. Toss to coat, adding more pasta cooking water as needed until the pasta is completely coated.
To serve:
Divide the pasta between shallow bowls. Garnish with the remaining grated parm and a few basil leaves. Finish each bowl with a drizzle of extra virgin olive oil if you like. Enjoy!
Notes
Note: You can leave the water boiling, add salt, and reuse it for the pasta. However, if you notice any grit in the water, I recommend dumping it, filling the pot back up with fresh water, and bringing it to a boil for the pasta.