Ingredients 
 2 tablespoons olive oil
 3/4 cup chopped sweet onion
 3/4 cup chopped fennel, fronds reserved
 3/4 cup chopped leeks
 1/2 plus 1/8 teaspoon salt
 1 plus 1/8 teaspoon fresh-ground pepper
 One 15-ounce can low-sodium chicken broth
 1/2 cup dry white wine
 2 tablespoons fresh thyme leaves
 1 pound peas, removed from pods (about 3 cups)
 3/4 cup red seedless grapes, halved (about 3 1/2 ounces)
 1/2 teaspoon lemon zest
 6 ounces low-fat plain yogurt
 1 tablespoon lemon juice

1. Make the soup: Heat olive oil in a large saucepan over high heat. Add the sweet onion, fennel, and leeks and sauté for 2 minutes. Add 1 teaspoon salt and 1/2 teaspoon ground pepper, lower heat to medium low, and cook until vegetables are tender — about 15 minutes. Add the broth, wine, and thyme and bring to a simmer. Cook for 10 minutes. Add the peas and simmer for 5 more minutes. Transfer the soup in batches to a blender and puree the soup until smooth. Add up to a 1/2 cup water to thin. Transfer to a large bowl, cover, and chill.

2. Make the Grape Salsa: Combine grapes, 1 tablespoon chopped fennel fronds, lemon zest, remaining salt, and pepper in a small bowl. To serve, whisk yogurt, 1/4 cup water, and lemon juice into the chilled soup. If necessary, thin with water to desired consistency. Serve soup cold, garnished with seasoned grapes.