3/4 cup chopped leek (white and pale green parts only)
2 garlic cloves, chopped
1/2 teaspoon chopped fresh thyme
1/4 teaspoon fennel seeds
5 cups (or more) canned low-salt chicken broth
Additional chopped fresh thyme
Directions
Melt 1/4 cup butter in large saucepan over medium-low heat. Add carrots, onion, leek, garlic, 1/2 teaspoon thyme and fennel seeds; stir to coat. Cover; cook until onion is translucent, stirring occasionally, about 15 minutes. Add 5 cups broth. Bring to simmer. Cover partially; simmer until carrots are very tender, stirring occasionally, about 40 minutes. Cool slightly. Working in batches, purée soup in blender. Return to pan. Thin to desired consistency with more broth. Season with salt and pepper. (Can be made 1 day ahead. Cool slightly. Cover and chill.)
Bring soup to simmer. Ladle into bowls. Sprinkle with additional thyme.
