We think bowls made of ice are the perfect vessel for this soup, but if space is tight in your freezer, regular soup bowls will work just fine.
Ingredients
2 medium onions, chopped
3 tablespoons olive oil
2 lb sugar snap peas, cut crosswise into 1/2-inch pieces
1 teaspoon sugar
6 cups plus 2 1/2 tablespoons water
2 teaspoons salt, or to taste
3 tablespoons sour cream
1 teaspoon finely grated fresh lemon zest
Garnish: pea sprouts
Directions
Cook onions in oil in a wide 6-quart heavy pot over moderately low heat, stirring occasionally, until softened, 5 to 7 minutes. Add sugar snaps and cook, stirring occasionally, until crisp-tender and bright green, 6 to 8 minutes. Add sugar and cook, stirring, 1 minute.
Purée pea mixture with 6 cups water in a blender in 6 batches until very smooth, about 30 seconds per batch, then pour through a very fine sieve, discarding solids (do not press on solids). Stir in salt and chill broth, covered, until very cold, about 8 hours. (Do not chill longer or soup will discolor.)
Whisk together sour cream, zest, and remaining 2 1/2 tablespoons water in a small bowl, then pour through a very fine sieve into another small bowl (to remove air bubbles).
