Preheat your oven to 400°F (200°C) and line a baking sheet with parchment paper.

Toss the diced butternut squash with 2 tablespoons of olive oil, salt, and pepper. Spread on the baking sheet and roast for 25-30 minutes, stirring halfway through.

Bring a large pot of salted water to a boil. Cook your pasta according to package instructions until al dente, reserving 1 cup of pasta water before draining.

In a large skillet, heat 1 tablespoon of olive oil over medium heat. Sauté the onion until translucent, then add garlic, sage, and red pepper flakes, cooking until fragrant.

Add the roasted butternut squash and vegetable broth to the skillet. Lightly mash some squash and stir in heavy cream or coconut milk and Parmesan until combined.

Toss the cooked pasta with the sauce, adding reserved pasta water as needed for desired consistency. Adjust seasoning with salt and pepper.

Serve the pasta garnished with toasted walnuts, extra Parmesan, and fresh sage leaves.