Ingredients

• 3 pounds lima beans in pods, shelled (scant 3 cups beans), or 2 (10-ounces) packages frozen baby lima beans, thawed
• 1 pound green beans, trimmed and cut into 1-inch pieces (5 cups)
• 4 cups water
• 2 1/2 cups reduced-sodium chicken broth
• 2 scallions, chopped
• 1/4 teaspoon ground cumin
• 1/8 teaspoon cayenne
• 1/4 cup packed flat-leaf parsley leaves
• 1/4 cup packed cilantro leaves
• 2 tablespoons dill leaves
• 2 tablespoons mint leaves
• 1/2 cup olive oil

Instructions

1. Simmer lima and green beans, water, broth, scallions, cumin, cayenne, and 1 teaspoon salt in a large saucepan over medium heat, covered, until beans are tender, about 15 minutes. Purée mixture in batches in a blender until very smooth (use caution when blending hot liquids). Force purée through a fine-mesh sieve into a bowl, discarding solids. Chill (covered once cool) until cold, about 1 hour.
2. While soup chills, purée herbs with oil and 1/4 teaspoon salt in cleaned blender.
3. Season soup with salt and pepper. Serve with herb oil swirled in.