01 - Preheat oven to 425°F. Toss squash cubes with olive oil, salt, and pepper. Spread on a baking sheet and roast for 25–30 minutes, turning once, until golden and tender. Set aside.
02 - Heat vegetable broth in a small saucepan over low heat and keep warm.
03 - In a large heavy-bottomed pot, melt 1 tbsp butter with 1 tbsp olive oil over medium heat. Add onion and cook for 3–4 minutes until translucent. Add garlic and cook 1 more minute.
04 - Stir in Arborio rice and cook, stirring frequently, for 2 minutes until lightly toasted.
05 - Pour in white wine and stir continuously until fully absorbed by the rice.
06 - Add warm broth in 1/2 cup increments, stirring frequently. Wait until each addition is mostly absorbed before adding more. Continue for about 20 minutes until the rice is creamy and al dente.
07 - Gently fold in roasted squash, remaining 1 tbsp butter, Parmesan, sage, salt, and pepper. Adjust seasoning to taste.
08 - Dish immediately, garnished with extra Parmesan and fresh sage if desired.