courtesy of Kay Chun, Food and Wine

This recipe is a fantastic showcase for superfresh summer squash. F&W's Kay Chun cuts zucchini and yellow squash lengthwise into ribbons on a mandoline, then tosses them with hot pasta so they just barely cook.

Ingredients
3/4 cup walnut halves
4 cups packed arugula leaves (4 ounces)
3/4 cup extra-virgin olive oil, plus more for drizzling
1/2 teaspoon finely grated garlic
1/2 cup freshly grated Parmigiano-Reggiano cheese, plus shavings for garnish
Kosher salt
Pepper
12 ounces pappardelle
3 firm, fresh medium zucchini and/or yellow squash (1 1/4 pounds), very thinly sliced lengthwise on a mandoline
3 tablespoons fresh lemon juice

Method

1. In a small skillet, toast the walnuts over moderately low heat until golden, about 
5 minutes. Finely chop 1/2 cup of the walnuts; coarsely chop the rest for garnish.
2. In a food processor, pulse 2 cups of the arugula until finely chopped; scrape into a large bowl and stir in the 3/4 cup of olive oil, the garlic, grated cheese and finely chopped walnuts. Season the pesto with salt and pepper.
3. In a large pot of salted boiling water, cook the pappardelle until al dente. Drain the pasta and add to the pesto in the bowl. Add the zucchini and toss to evenly coat. Stir 
in the lemon juice and the remaining 2 cups of arugula and season with salt and pepper. Transfer the pasta to a platter, drizzle with olive oil and garnish with the coarsely chopped walnuts and cheese shavings.