Use a fork to poke holes in the sweet potato. Cook in the microwave on high for 5-8 minutes until soft. When cool enough to handle, peel the sweet potato.
Meanwhile, in a skillet over medium heat sauté the onion and garlic in the oil until translucent.
Blend the peeled sweet potato, onion and garlic mixture, and heavy cream in a high speed blender.
Cook the Veggiecraft Rotini according to the package directions.
Return the sauce to the pan. Stir in the parmesan and salt, and allow the cheese to melt.
Add the cooked pasta to the pan with the sauce and stir to coat.
If desired, arrange the rotini into a pumpkin shape. Use two leaves of sage for the pumpkin stem. Alternatively, plate and garnish with sage.