1. Preheat oven to 400°F (200°C) and line a sheet pan with parchment paper.

2. Toss cubed squash, chopped onion, and unpeeled garlic cloves with 3 tablespoons olive oil, salt, and pepper. Spread in a single layer.

3. Roast for 30–35 minutes, turning once, until vegetables are caramelized.

4. Let roasted vegetables cool slightly, then squeeze garlic from skins.

5. Blend roasted squash, onions, garlic, and 2 cups broth until smooth, adding more broth to reach desired consistency.

6. Transfer soup to a large pot, stir in remaining broth, nutmeg, and heavy cream. Simmer on low for 10 minutes, stirring occasionally.

7. Meanwhile, increase oven to 375°F (190°C). Toss bread cubes with 1 tablespoon olive oil, salt, pepper, and any optional seasonings.

8. Spread croutons on a baking sheet and bake for 10–15 minutes, turning once, until golden and crisp.

9. Ladle soup into bowls and top each with a handful of homemade croutons and fresh herbs.

10. Serve immediately.