2 cups baby arugula
1 tablespoon lemon zest
1 tablespoon minced garlic
1 cup toasted walnut pieces, divided
3 tablespoons olive oil
1/2 teaspoon kosher salt
1/4 teaspoon pepper
3/4 cup crumbled gorgonzola cheese
1/2 cup golden raisins
Cook pasta according to package directions. Whirl together arugula, zest, garlic, 1/4 cup walnuts, the oil, salt, and pepper in a food processor until blended, scraping inside of bowl as needed. Drain pasta, reserving about 1/4 cup of the water. Return pasta to pot and add pesto, stirring to coat. Stir in remaining walnuts, the cheese, raisins, and reserved pasta water.