Ribbons of savory spinach, chunks of tender summer squash, fragrant basil leaves and fresh mozzarella form a tasty medley for a quick pasta dinner.
Finished with a zesty gremolata and plenty of Parmesan cheese, it's a delicious vegetarian meal with tons of summertime flavor.
To make the gremolata, add the parsley, lemon zest, and capers to a small bowl and stir to combine thoroughly. Set aside. (The mixture can be refrigerated, covered, if you’re making it several hours ahead of using.)
Bring a large pot of water to a boil over high heat. Add 1 to 2 tablespoons of salt and the linguine. Cook the pasta al dente: just tender but still firm to the bite. Reserve at least 1 cup of the cooking liquid and drain.
Meanwhile, heat the oil in a large skillet over medium heat. Add the crushed red pepper and shallots, and cook, stirring frequently, until the shallots begin to soften, about 2 minutes. Add the squashes and raise the heat to medium-high. Cook, stirring occasionally, until the squash is barely crisp-tender, about 3 to 4 minutes. Add the garlic and cook until fragrant, about 1 minute. Season the vegetable medley with salt and pepper to taste.
Using tongs, transfer the linguine to the skillet, and add about 1/2 cup of the pasta cooking liquid. Stir in the spinach and basil, and cook until the greens wilt, 1 to 2 minutes. Add the Parmesan and mozzarella cheeses and 1/2 cup of the pasta cooking liquid, or more if the mixture seems dry. Cook until the mozzarella just begins to melt, about 1 minute, then remove the skillet from the heat. Stir in the gremolata and serve immediately, with more Parmesan as garnish, if desired.