Step 1: Preheat your oven to 400°F (200°C). Carefully slice off the top 1/4 to 1/2 inch of each mini pumpkin to create a 'lid'. Scoop out the seeds and stringy pulp. Drizzle the inside and cut edges of each pumpkin with olive oil, and season lightly with salt and pepper.
Step 2: Place the pumpkins (and their lids, if desired) on a baking sheet. Roast for 30-40 minutes, or until the pumpkin flesh is tender when pierced with a fork. Set aside.
Step 3: While pumpkins are roasting, bring a large pot of salted water to a boil. Add the fettuccine or spaghetti and cook according to package directions until al dente. Drain, reserving about 1 cup of the pasta cooking water.
Step 4: In a large skillet or pot, melt the butter over medium heat. Add the minced garlic and sauté for 1 minute until fragrant, being careful not to brown it.
Step 5: Pour in the heavy cream and bring to a gentle simmer. Reduce the heat to low and stir in the Parmesan cheese until melted and the sauce is smooth. If the sauce is too thick, add a splash of the reserved pasta water.
Step 6: Stir in the optional pinch of nutmeg, then add the cooked and drained pasta to the sauce. Toss to coat evenly. Season with salt and pepper to taste.
Step 7: Carefully spoon the creamy pumpkin alfredo pasta into each roasted mini pumpkin cauldron. Garnish with chopped fresh parsley and toasted pumpkin seeds (pepitas). Serve immediately and enjoy your festive fall meal!