Step 1: Preheat your oven to 400°F (200°C). Toss the cubed butternut squash with olive oil and salt on a baking sheet.
Step 2: Slice the top off the head of garlic to expose the cloves, drizzle with oil, wrap in foil, and place on the same baking sheet. Roast for 30 minutes until squash is tender and garlic is soft.
Step 3: Squeeze the roasted garlic cloves out of their skins and mash into a paste. Set aside with the roasted squash.
Step 4: In a large pot, melt 2 tablespoons of butter over medium heat and sauté the minced shallots until translucent.
Step 5: Add the Arborio rice to the pot and cook for 2 minutes, stirring constantly to toast the grains.
Step 6: Pour in the white wine and stir until the liquid is fully absorbed by the rice.
Step 7: Add the warm vegetable broth one ladle at a time, stirring frequently. Wait for each ladle to be absorbed before adding the next.
Step 8: When the rice is nearly al dente (about 20 minutes), stir in the roasted garlic paste and the roasted butternut squash chunks.
Step 9: Remove from heat. Stir in the remaining tablespoon of butter and the Parmesan cheese. Season with salt and pepper, and garnish with fresh sage.