Step 1

Heat oven to 400ºF. Peel and seed the squash. Cut into 1-inch cubes and place them on a rimmed baking sheet. Drizzle with 1 tablespoon olive oil, salt, and pepper; toss to coat. Spread in a single layer and roast for 15 minutes. Turn and continue to roast until softened, about 20-25 minutes more.

Step 2

Meanwhile, heat the remaining 1 tablespoon oil in a stockpot or Dutch oven over medium heat. Add onion and celery, and cook until softened, about 7 minutes. Add sage and saute 1 minute more.

Step 3

Add broth and roasted squash and bring to a boil. Reduce heat and simmer for 30 minutes, or until vegetables are very tender. Remove from heat. Let cool for about 10 minutes. Use a handheld (immersion) blender to blend soup directly in the pan. Return to stove and warm over medium-low heat. Add broth as needed to thin as desired. I typically add about 1 cup.

Step 4

Taste and add salt and pepper as needed.