Wash and pat dry 800 g zucchini then cut into thin slices.
Heat 120 ml olive oil in a heavy bottom/iron skillet and lightly fry zucchini slices on either side till golden. Fry them in batches transferring the fried zucchini to a kitchen towel to drain excess oil.
Boil 400 g spaghetti in a large saucepan of salted boiling water (stirring occasionally), for 1 minute less than cooking time advised on the pasta packaging. Drain the pasta reserving around 240ml/1 cup pasta water for the zucchini sauce.
In the same skillet heat 2 tablespoons olive oil and 2 cloves garlic till garlic turns pale gold, then add the fried zucchini and reserved pasta water. Bring to a boil then mix in 2 tablespoons butter and season with 1 teaspoon salt and ¼ teaspoon freshly ground black pepper.
Add the spaghetti to the skillet and toss well with zucchini sauce on low heat for 1 minute. Remove from the heat and stir in 100 g Provolone cheese and 100 g Parmigiano Reggiano cheese. Mix well till the cheese melts making a cheesy sauce then garnish with 5 fresh basil leaves (optional) and serve immediately.
Notes
800g is equivalent to 4 medium zucchini. Medium size zucchini have more flavour than larger ones and less water so they will cook quicker.Pasta water adds a rich creaminess to the sauce.*Pro tip: Use the spiky star-shaped side of the grater when grating the cheeses so they melt easily and evenly coat the pasta.Make ahead - Zucchini can be fried in advance, then cooled and kept in a closed container in the fridge for up to 3 days before using.Storing - Store leftover pasta in a closed container and keep in the fridge for up to 3 days. Bring to room temperature or reheat in a saucepan with 1-2 tablespoons water before serving.