Chilled Yogurt-Spinach Soup with Shrimp

INGREDIENTS

• 1 1/2 cucumbers (about 1 pound), peeled, seeded, and cut into 1-inch pieces
• 2 containers (7 ounces each) plain low-fat Greek yogurt (2 percent)
• 1 3/4 cups low-sodium store-bought chicken broth
• 2 scallions (white and pale-green parts cut crosswise into 1/2-inch pieces, dark-green parts julienned)
• Coarse salt and freshly ground pepper
• 1 tablespoon olive oil
• 2 cloves garlic, minced
• 5 ounces baby spinach
• 1 tablespoon finely chopped plus 1 teaspoon red onion
• 1 tablespoon plus 1 teaspoon, freshly squeezed lemon juice
• 1 pound rock shrimp, rinsed well