Preheat oven to 400 degrees F.

Cut squash in half and scrape out seeds. Discard seeds or roast them separately as you would with pumpkin seeds.

Slice squash into 1-inch strips. Drizzle 1 tablespoon olive oil over the squash and toss to coat. Place the squash strips on a baking sheet and roast until tender, about 30 minutes.

While the squash is roasting, heat remaining 1 tablespoon olive oil and 1 tablespoon butter in a heavy bottom saucepan over medium heat.

Add onion and cook until softened and opaque, stirring occasionally. Add garlic and allspice, stir, and cook until fragrant (about 1 minute).

Add rice and stir to combine. Continue stirring and cooking until the edges of the rice are translucent and the center is still opaque, about 2 minutes.

Add wine and stir to combine. Cook until the rice absorbs the wine, stirring occasionally.

Add warm broth, a ladle at a time, stirring after each addition and occasionally stirring while cooking. Wait to add each ladle of broth until the rice has almost soaked up the last addition.

Test the rice after you have added about 3 cups of broth to see if it is done. It should be al dente, with just a bit of chew to it and not completely soft or mushy.

Note the risotto will not taste fully seasoned at this point. It will get saltiness from the parmesan cheese.

The risotto is ready when it is similar to a thick porridge and have a creamy consistency.

Add one more ladle of broth, remaining 2 tablespoons butter, and parmesan cheese. Stir to combine.

Cut the roasted squash into bite-sized chunks and gently stir into the risotto. Serve immediately.