In a large pot of salted boiling water, cook the fettuccine according to package directions until al dente. Reserve 0.5 cup of the pasta cooking water, then drain the pasta and set aside.
In a large skillet over medium heat, melt the butter. Add the minced garlic and sauté for about 1 minute until fragrant, being careful not to burn it.
Stir in the pumpkin puree, heavy cream, and chopped sage. Mix well to combine. Let it simmer gently for about 3-4 minutes, allowing the flavors to meld together.
Gradually whisk in the grated Parmesan cheese until the sauce becomes creamy and smooth. Add nutmeg, and season with salt and black pepper to taste.
Add the cooked fettuccine to the sauce in the skillet. Toss well to coat the pasta evenly, adding reserved pasta water a little at a time if the sauce needs to be loosened.
Divide the pasta into bowls, and garnish with toasted pumpkin seeds and extra sage leaves if desired. Enjoy your warm, cozy dish!
Notes
Optional: garnish with toasted pumpkin seeds and extra sage leaves.