Roasted Root Vegetable Soup with Rosemary Walnuts

1. Prepare soup: Preheat oven to 400 F. Line two large baking trays with parchment or foil and add a tablespoon of olive oil to each. Spread the oil evenly.
2. Peel sweet potatoes, russet potato, carrots and parsnip. Cut vegetables into approximately 1 1/2-inch chunks. Spread onions on one tray, along with the carrots and potato, all in a single layer. Slice the topmost tips from the garlic head; add to tray with potato, onions and carrots.
3. Scatter sweet potato and parsnip pieces on second tray. Place both trays in preheated oven; roast vegetables 20 to 40 minutes until fork-tender and brown around the edges. (You might need to loosen the pieces from time to time by shaking the trays and/or lifting vegetables with a small spatula.) Roast garlic until cloves are soft enough to give when squeezed; cool.
4. Meanwhile, gently heat broth in a covered soup pot.
5. Add roasted vegetables to heated broth. Squeeze roasted garlic pulp into soup; discard peel. Cover and simmer over low heat about 15 minutes. Cool slightly, then puree in blender or food processor until creamy. Season to taste with salt and pepper.
6. Prepare rosemary walnuts: Heat wide skillet over medium heat. Add olive oil; swirl to coat pan.
7. Add walnuts and rosemary; reduce heat to low. Pan-roast walnuts 5 to 10 minutes until deep golden brown. Season with salt to taste.
8. To serve, sprinkle walnuts on each bowl of soup.

Photo courtesy of California Walnuts