Preheat oven to 400°F.
Toss the Butternut Squash “Rotini” in olive oil, salt, and pepper. Spread it evenly on a lined baking sheet and roast until tender and slightly browned, about 20 minutes.
To make the sauce, melt 2 tablespoons of butter in your smallest saucepan over medium-low heat. Add the minced garlic and let it cook until softened and pieces are just starting to turn golden. Remove the softened garlic and set aside.
Add the rest of the butter to the pan along with the sage leaves and walnuts, and cook over low-heat, stirring occasionally until the butter has browned and the sage leaves are crisp and intoxicatingly fragrant.
Remove from heat and stir back in the softened garlic.
Move Butternut Squash “Rotini” from baking sheet to serving dish.
Lastly, drizzle sauce with walnuts and sage evenly over squash, tossing gently.