Preheat your oven to 400°F (200°C). In a mixing bowl, toss the cubed butternut squash with olive oil, salt, and pepper until well coated. Spread the squash on a baking sheet and roast for 20 to 25 minutes, stirring once halfway through.

While the squash roasts, pour the vegetable or chicken broth into a small saucepan and bring it to a gentle simmer over low heat. Keep the broth warm throughout the cooking process.

In a large skillet, heat 2 tablespoons of olive oil over medium heat. Add the diced onion and cook for about 5 minutes until soft. Stir in the minced garlic and sauté for an additional minute.

Add the Arborio rice to the skillet, stirring to coat each grain with the oil. Sauté for 1 to 2 minutes until the rice is slightly toasty and translucent.

Begin adding the warm broth, one ladle at a time. Stir gently and let the rice absorb the liquid before adding more. Continue until the rice reaches a creamy texture, about 18 to 20 minutes.

Once the rice is cooked, fold in the roasted butternut squash and chopped sage. Remove from heat and stir in the grated Parmesan cheese and optional butter until glossy and smooth.

Spoon the risotto into bowls and garnish with extra Parmesan and fresh sage leaves. Serve immediately.