Pre-heat oven to 300°F. Place Pane Turano on a baking sheet and place in the oven for 15 minutes. Take the Pane Turano out of the oven and let it cool for 10 minutes. Place bread in a sealed bag. Smash with a rolling pin to make bread crumbs. In a large pan, over medium heat, heat about 2 tablespoons of olive oil. Sauté the garlic until fragrant, 1-2 minutes. Reduce heat to medium low and add the breadcrumbs. Add 2 more tablespoons of olive oil and combine. Stir together for about 2 minutes. Add the chopped walnuts and stir for another 2 minutes. Add raisins and basil. Combine. Set aside. Bring a large pot of salted water to a boil. Add the spaghetti and cook until al dente, per package instructions. Drain the pasta and reserve about 1 cup of the cooking water. Add to the breadcrumb mixture, and add 2 more tablespoons of olive oil. In a large serving dish, alternate layers of pasta and bread mixture, topping with the bread mixture. Garnish with basil and drizzle with remaining olive oil.