In a large skillet or Dutch oven, heat 2 tablespoons of olive oil over medium heat. Add one finely chopped onion and sauté for about 5–7 minutes until translucent.

Stir in 2 minced garlic cloves and 1 tablespoon of fresh sage, cooking for approximately 1 minute until aromatic.

Add 1 cup of pumpkin puree to the pan, stirring well to combine. Cook for 2–3 minutes.

Pour in 1 cup of heavy cream and add ½ cup of grated Parmesan cheese, stirring until smooth and creamy.

Season the pumpkin sauce with salt, black pepper, and red pepper flakes. Reduce heat and let simmer for about 10–15 minutes.

Cook pasta in salted water according to package instructions. Reserve ½ cup of pasta cooking water before draining.

Toss drained pasta into the pumpkin sauce, stirring gently to coat. Add reserved pasta water as needed.

Fold in half of the crumbled feta cheese and drizzle in 1 tablespoon of melted butter, mixing gently.

Serve hot, garnished with remaining feta cheese and toasted pumpkin seeds.