Bring a large pot of well-salted water to a boil. Cook fusilli until al dente, 8–10 minutes. Reserve 1/2 cup pasta water, then drain.

Heat 2 tbsp olive oil in a large skillet over medium heat. Add diced zucchini and cook 5–7 minutes, stirring occasionally, until golden on edges and tender. Transfer to a plate.

In the same skillet, add cherry tomatoes, black pepper, fennel seed, garlic powder, cayenne (optional), and 1/4 cup vegetable broth. Cover and cook over medium heat, stirring occasionally, 5–7 minutes until tomatoes blister and soften but keep their shape.

Push tomatoes to one side. Add cooked zucchini, pasta, and 1 cup grated Parmesan. Toss over low heat 2–3 minutes until cheese melts and coats the pasta; add a splash of broth or reserved pasta water for a silky sauce.

Serve hot. Drizzle with a little olive oil, sprinkle extra Parmesan, garnish with basil or parsley, and finish with crushed chili flakes if desired.