In a medium pot, bring 6 cups of water to boil. Add pasta and cook for about 10 minutes, until al dente. Drain the water and set aside.
In a large skillet heat the olive oil over medium-high heat. Stir in minced garlic and sauté for about 3 minutes, until lightly brown and fragrant. Add sage and sauté for another minute. Pour in pumpkin puree, vegetable broth, allspice, salt and pepper and bring to a boil. Reduce heat to a simmer and simmer for 7-9 minutes, stirring almost constantly, until sauce begins to thicken. Remove from heat and stir in almond milk.
Stir in pasta and sauce and top with hazelnuts, scallions, and vegan parmesan cheese. Serve immediately.