Preheat your oven to 375°F (190°C) and grease a medium-sized baking dish.

In a large pot, cook the pasta in salted boiling water until al dente, about 8–10 minutes. Reserve a cup of pasta water before draining.

In a large skillet over medium heat, add olive oil and sauté the chopped onion until translucent, about 5 minutes.

Add minced garlic, cooking for another minute, then stir in pumpkin puree, ricotta, nutmeg, salt, and black pepper.

Gradually stir in broth to achieve desired sauce consistency, using reserved pasta water if necessary.

Add fresh spinach to the skillet, stirring gently until wilted, about 2–3 minutes.

Combine drained pasta with the pumpkin-ricotta sauce in a large mixing bowl, stirring until well-coated.

Transfer pasta mixture to the prepared baking dish, smoothing the top.

Sprinkle grated mozzarella and Parmesan cheese on top, pressing down lightly to adhere.

Bake for 20–25 minutes until the cheese is melted, bubbly, and lightly golden.

Let the pasta bake rest for 5–10 minutes before serving, optionally garnished with fresh basil leaves.