Preheat the oven to 200°C (400°F). Cut the zucchini into 1/2 inch coins; scoop the seeds from thick, seedy parts, then halve and slice them. Toss on a rimmed baking sheet with olive oil, salt, Italian seasoning, chili flakes and some lemon zest, then spread out evenly. Roast in the upper third of the oven for about 20 minutes, tossing halfway, until the edges brown. Let cool. Meanwhile, cook the pasta in well salted water until al dente, drain and return to the pot. Once cooled slightly, stir in the creme fraiche, remaining lemon zest, half the goat cheese, a handful of parsley, salt, pepper and nutmeg. Fold in the zucchini. Transfer to a buttered baking dish, top with the remaining goat cheese, parmesan and more parsley. Bake for 15-20 minutes until melted and bubbly. Rest for 5-10 minutes before serving.