Spaghetti Alla Nerano

Name: Spaghetti Alla Nerano
Ingredients: Kosher salt; 1/2 cup extra-virgin olive oil; 2 pounds small zucchini (4 to 5), very thinly sliced into rounds, about 1/8 inch thick; 12 ounces spaghetti; 1 tablespoon unsalted butter; 1/3 cup freshly grated Parmesan cheese, plus more for topping; 1 cup torn basil, plus 1/2 cup small whole leaves for topping