SQUASH AND SWEET-POTATO SOUP WITH CHIPOTLE SAUCE

Steps:

• Preheat oven to 400°F.
• Brush cut sides of squash with 1/2 teaspoon oil and arrange, cut sides down, in a shallow baking pan. Prick sweet potatoes all over with a fork and roast with squash until very tender, about 50 minutes for squash and about 1 1/4 hours for sweet potatoes.
• Cool vegetables and scoop flesh from squash into a bowl. Peel sweet potatoes and add to squash.
• Cook onion in remaining 2 1/2 teaspoons oil with salt to taste in a 6-quart heavy pot over moderately high heat, stirring occasionally, until golden brown, about 10 minutes. Stir in squash and sweet potato, leek, ginger, and 8 cups stock and simmer, uncovered, stirring occasionally, 30 minutes.
• Purée in batches in a blender (use caution when blending hot liquids), transferring to a clean pot. Bring to a simmer and, if too thick, add more stock. Season with salt and white pepper. Finish with lemon juice and, if desired, honey.
• Serve soup drizzled with some chipotle sauce or swirl sauce in to make a pattern.