Cheese Soup (Cooks Illustrated)

This soup isn't the best candidate for making in advance. Reheat the soup in a saucepan over low heat, whisking gently to prevent the soup from separating. Do not bring above a bare simmer. 

3 tablespoons unsalted butter
1 medium onion, minced (about 1 cup)
1 medium carrot minced (about 1/3 cup)
1 medium celery rib, minced (about 1/4 cup)
1 medium garlic clove, minced or pressed through garlic press (1 teaspoon)
2 tablespoons unbleached all-purpose flour
2 1/2 cups low-sodium chicken broth
2 1/2 cups half-and-half
1 bay leaf
pinch cayene
3 tablespoons dry sherry
12 ounces sharp cheddar cheese, shredded (about 3 cups)
1 tablespoon minced fresh thyme leaves
table salt and ground black pepper
Cheese Soup
1. Heat butter in large heavy-bottomed Dutch oven over medium heat until foaming; add onion and cook, stirring occasionally, until softened about 4 minutes. Add carrot, celery, and garlic; cook until garlic is fragrant, about 1 minute. Add flour and cook, stirring to coat vegetables, until mixture begins to brown on bottom of pot, about 2 minutes. Gradually whisk in chicken broth and half-and-half and add bay leaf. Increase heat to medium-high and bring to boil; reduce heat to medium-low and simmer until vegetables soften about 10 minutes.

2. Off heat, add cayenne and sherry; cool soup for 1 minute. Slowly whisk in cheese and thyme; season with salt and pepper and serve immediately.