How to Make It
In a food processor with the motor running, drop in the garlic and finely chop. Add the nuts, cheese, 1 teaspoon salt and 1/2 teaspoon pepper and pulse to finely chop. Add the basil. With the motor running, add the oil, blending to combine.
In a large pot of boiling salted water, cook the pasta until al dente. Reserve 3/4 cup of the pasta cooking water, then drain the pasta. Toss the pasta with the pesto and about half the reserved cooking water. Add more water for a looser consistency.
Cut the ends from the zucchini. Using a vegetable peeler, make ribbons from the zucchini.
In a medium heavy skillet, heat the butter over medium heat until hot. Stir in the breadcrumbs and fry until golden, 1 to 2 minutes. Season the breadcrumbs with salt and pepper to taste. Toss the zucchini ribbons with the pasta, then sprinkle with the bread crumbs. Season with salt and pepper to taste, then serve.