Spaghetti with Tomato and Walnut Pesto

Name: Spaghetti with Tomato and Walnut Pesto
Ingredients: 2/3 cup walnuts; 2 pints cherry tomatoes, halved; 2 tablespoons plus 1/3 cup olive oil, plus more for drizzling; Kosher salt; 6 oil-packed anchovies, coarsely chopped; 2 garlic cloves, coarsely chopped; 1 teaspoon finely grated lemon zest; 1/4 teaspoon crushed red pepper flakes; 1/2 ounce Parmesan, finely grated (about 1/2 cup), plus more for serving; 1 teaspoon freshly ground black pepper; 12 ounces spaghetti; 1/2 cup (packed) basil leaves