Preheat Blackstone griddle to medium heat. Drizzle vegetable oil then add the onion, garlic, chicken, and squash. Cook for 12-15 minutes, stirring constantly until the chicken is cooked and the squash is tender.
Add the pasta, pumpkin, and alfredo sauce directly to the griddle. Stir with spatulas until well incorporated. Cook for an additional 3 minutes until the sauce slightly reduces and coats the pasta.
Remove the pasta from the griddle and place on a large serving plate. Top with shredded parmesan, serve immediately.
