Warm Cucumber Soup with Scallop and Sole Mousselines

Ingredients

• 0.3 teaspoon pepper black
• 0.5 cup carrots chopped
• 3 large cucumber seedless quartered (usually plastic-wrapped; 3 pounds total)
• 10 servings optional: dill smoked fresh black thinly sliced ( cod)
• 1 large garlic clove chopped
• 1 medium onion chopped
• 0.3 pound baking potatoes (baking)
• 1.5 teaspoons salt 
• 10 servings sole 
• 1 sprig thyme sprigs fresh (3-inch)
• 1  bay leaves 
• 2 tablespoons butter unsalted
• 4 cups water 

Equipment

• bowl
• sauce pan
• pot
• sieve
• blender
• stove
• microwave
• colander

Directions

1. Cook cucumbers in a 4- to 5-quart pot of boiling salted water, uncovered, just until water returns to a boil, about 1 minute, then immediately drain in a colander and transfer to a bowl of ice and cold water to stop cooking.
2. Drain cucumbers well, then purée in 2 batches in a blender until as smooth as possible, about 1 minute, transferring to a bowl.
3. Peel potato and cut into 1/2-inch cubes. Cook onion, carrot, celery, garlic, bay leaf, and thyme in butter in a 2-quart heavy saucepan over moderate heat, stirring occasionally, until vegetables are softened, about 3 minutes.
4. Add potato, 4 cups water, pepper, and 1/2 teaspoon salt and simmer, partially covered, until potato is very tender, about 15 minutes. Discard bay leaf and thyme.
5. Purée mixture in batches in blender until very smooth, about 1 minute (use caution when blending hot liquids), transferring to a large bowl. Chill, uncovered, until completely cool, about 30 minutes.
6. Stir cucumber purée into potato purée and force soup through a fine-mesh sieve into a large bowl, pressing hard on and then discarding solids.
7. Stir remaining teaspoon salt into soup, then reheat in a bowl in a microwave or in a saucepan on stovetop over low heat (microwaving is best because it preserves the soup's bright green color). Put 1 mousseline in each of 10 shallow soup bowls and pour warm soup around each.
8. Soup can be made 2 days ahead and chilled, covered.